VPN Not Working on Phone: 8 Fixes for Android and iOS

In short: VPN on your phone most commonly stops working due to an outdated app, the wrong protocol, or battery optimization that kills the VPN process in the background. Restart the app, switch to WireGuard, and remove battery restrictions — in 80% of cases the connection is restored within 5 minutes.

If the issue is Android-specific, read the detailed breakdown in VPN not working on Android. For iPhone, there is a separate in-depth guide: VPN not working on iPhone. This article covers both mobile platforms and helps you find the root cause when you are not sure where to start.

Important: the problem is almost never permanent. Most cases come down to one of eight technical issues explained below. Follow the diagnostic steps, and the connection will be restored.

Quick Diagnosis in 5 Steps

Before diving into settings, run through these five quick steps — they solve the majority of problems in 5 minutes without any technical background.

1. Restart the VPN app. Close the app completely (from the recent-apps list), do not just minimise it. Reopen and tap Connect.
2. Update the app and the OS. An outdated version is the number-one cause of sudden failures. Open the app store and update the VPN client. Check for pending OS updates as well.
3. Switch the protocol. In the app settings, choose a different protocol: try WireGuard, IKEv2, or OpenVPN. The current protocol may be incompatible with your network settings.
4. Check battery optimization. If VPN disconnects in the background, the system is saving battery at the VPN process's expense. Remove restrictions for the VPN app (see Cause 3 below).
5. Reinstall the app. If nothing works, delete the app completely and reinstall it. The profile will refresh and old configurations will reset.

Diagnose by Symptom: What Exactly Is Not Working?

Different symptoms point to different causes — use this table to find the right section immediately.

Symptom	Likely Cause	Quick Fix
VPN won't connect, spinning indefinitely	Wrong protocol or server overloaded	Switch to WireGuard or IKEv2
VPN connected but no internet	Kill switch, DNS leak, or MTU issue	Disable kill switch; set DNS to 1.1.1.1
VPN disconnects on its own after a few minutes	Battery optimization kills the process	Remove battery restrictions for the VPN app
VPN works on Wi-Fi but not on 4G/5G	Carrier restricts the protocol or UDP ports	Switch to IKEv2 or OpenVPN TCP
After iOS update VPN won't connect	Old VPN profile incompatible with new OS	Delete the profile in settings, re-add it
App freezes at "Connecting..."	Conflict with Private DNS or another VPN	Disable Private DNS; delete duplicate profile

Cause 1. Outdated App or iOS/Android Version

This is the most common cause of sudden failures. Phone manufacturers regularly change network APIs in OS updates, and an old version of the VPN client can stop working after a routine system update.

Android: How to Update

Open Google Play → tap your profile icon → Manage apps & device → Updates available. Find the VPN app and tap Update. Also check for an OS update: Settings → About phone → Software update. Restart the device after updating — some changes require a reboot to take effect.

iOS (iPhone): How to Update

App Store → your profile icon (top right) → scroll down to the apps list → find the VPN app → Update. Check iOS version at Settings → General → Software Update. After a major iOS update, it is especially important to reconnect VPN or reinstall the app: some system permissions are reset during large updates.

Cause 2. Wrong VPN Protocol

Different protocols behave differently on mobile networks — and one may be incompatible with your connection's settings.

• WireGuard — fastest and most battery-efficient on mobile. Runs over UDP, establishes connections in milliseconds. Best choice for everyday use.
• IKEv2/IPsec — built into iOS and Android, supports MOBIKE fast-reconnect technology when switching networks. Optimal when you frequently switch between Wi-Fi and mobile data.
• OpenVPN TCP — the most "permissive" on restrictive networks: traffic on port 443 looks like ordinary HTTPS. Use it when WireGuard and IKEv2 fail on a specific network.

If VPN won't connect, switch the protocol and try again. Mobile carriers can restrict certain protocols or UDP ports in their network. Detailed comparison: VPN protocols: WireGuard, OpenVPN, IKEv2.

Cause 3. Battery Optimization Kills VPN in the Background

This is a unique mobile problem that competitors rarely mention. Android and iOS restrict background activity to save battery — and the VPN process can become a victim of that optimization.

Symptom: VPN works while the screen is on, but the connection drops a few minutes after you lock the screen. Especially noticeable overnight or after long idle periods.

Android: Settings by Manufacturer

The path depends on your firmware:

• Stock Android: Settings → Apps → [VPN app] → Battery → select "Unrestricted" or "Allow background activity".
• Samsung (One UI): Settings → Device Care → Battery → App power management → [VPN app] → "Unrestricted".
• Xiaomi (MIUI / HyperOS): Settings → Apps → [VPN app] → Battery → "No restrictions". Also: Security → Manage background activity → [VPN] → "No restrictions".
• OnePlus (OxygenOS): Settings → Battery → Battery optimization → [VPN app] → "Don't optimize".

Additionally: enable Always-On VPN on Android (Settings → Network & internet → VPN → [your VPN] → Always-On VPN). This mode restores the connection automatically when the network changes and partially overrides Android's Doze mode restrictions.

iPhone: iOS Background Mode Restrictions

iOS uses a special background model: VPN extensions have privileged system rights (Network Extension) that are not subject to standard battery restrictions. However, there are nuances:

• iCloud Private Relay conflicts with VPN. If you have an iCloud+ subscription and Private Relay is enabled, it may intercept traffic in parallel with your VPN. Disable it: Settings → [your name] → iCloud → Private Relay → turn off. This is the one iOS setting that systematically conflicts with most VPN apps.
• Always-On via corporate MDM profiles. If an employer's MDM profile is installed on the device, it may block third-party VPNs. Check: Settings → General → VPN & Device Management.
• iOS update resets permissions. After a major OS update, delete the VPN app and reinstall it — this restores Network Extension system permissions.

Cause 4. Conflict with Private DNS or Another VPN Profile

Two simultaneously active DNS routing mechanisms are a classic source of the "VPN connected but nothing loads" problem.

Android: Private DNS

Android 9+ has a built-in Private DNS feature (DNS-over-TLS). When it is active alongside VPN, DNS requests can conflict: some go through the VPN tunnel, others through the system DNS. To disable: Settings → Network & internet → More → Private DNS → select "Off". Then reconnect VPN. More on encrypted DNS: encrypted DNS: DoH and DoT.

iOS: Deleting Old VPN Profiles

VPN profiles accumulate on iPhone: when you reinstall the app or change your subscription, old profiles may remain active. Two active profiles guarantee a conflict. Delete all old profiles: Settings → General → VPN & Device Management → VPN configurations → delete all except the current one. Then re-add your subscription through the app.

Cause 5. VPN Connected but Internet Does Not Work

Connection is established (VPN icon is lit) but pages won't load. Three technical reasons with different solutions.

• Kill switch blocked traffic. Kill switch is a feature that blocks all traffic when the VPN tunnel drops. If the connection is unstable and the kill switch fires constantly — temporarily disable it in VPN app settings. Re-enable it once you confirm stability. More: what is VPN kill switch.
• DNS leak. The VPN tunnel is active but DNS requests bypass it through your ISP. Check: open a browser and visit ipleak.net with VPN active. If your ISP's address appears there — there is a leak. Fix: enable "DNS leak protection" in VPN app settings.
• MTU issue. VPN adds headers to packets, reducing the effective MTU. On mobile networks this is especially noticeable: small pages load, large ones do not. Try switching the protocol (WireGuard → IKEv2) — they have different header sizes.

Cause 6. VPN Disconnects on Its Own

If VPN connects but drops after a few minutes without any action from you — several causes are possible.

• Unstable internet connection. VPN runs on top of your connection. On weak Wi-Fi or poor 4G coverage, the tunnel drops. Check your base connection: disable VPN and test the speed. If internet is unstable on its own — VPN cannot help here.
• Overloaded server. Switch to a different server in the app — choose another node or the nearest one geographically. An overloaded server drops connections.
• Battery optimization — see Cause 3 above. This is the most common cause of sudden drops on mobile specifically.
• Always-On VPN. Enable "Always-On VPN" in Android system settings: Settings → Network & internet → VPN → [your profile] → Always-On VPN. The system will restore the connection automatically.

If VPN works on Wi-Fi but not on mobile data — that is a separate topic: VPN not working on mobile data.

Cause 7. Conflict with Another App

Some apps are incompatible with VPN tunnels and can block their operation.

• Antivirus or firewall. Some mobile antivirus apps (especially those with a built-in VPN module) conflict with third-party VPN clients. Temporarily disable the antivirus and check the connection. If VPN works — add the VPN app to the antivirus whitelist.
• MDM profile (corporate device management). On work phones, an MDM profile may block third-party VPNs or configure its own. Check: iOS → Settings → General → VPN & Device Management; Android → Settings → Security → Device administrators.
• Another VPN app. Two VPN clients cannot run simultaneously. Make sure no second VPN profile is active in the system. On Android: Settings → Network & internet → VPN — only one should be active.

On split tunneling, which lets you control which apps route through VPN: VPN split tunneling explained.

Step-by-Step Fixes: Android vs iPhone

If the quick diagnosis did not help, go through the full checklist for your OS.

Android (7 Steps)

1. Check your base connection. Disable VPN, open any website. If it does not load — the issue is with your internet, not VPN.
2. Disable Private DNS. Settings → Network & internet → More → Private DNS → Off. Reconnect VPN.
3. Check for duplicate VPN profiles. Settings → Network & internet → VPN. Make sure only one profile is active.
4. Switch the protocol. In LiMP VPN settings, select a different protocol (WireGuard, IKEv2, OpenVPN). Reconnect.
5. Remove battery restrictions. Settings → Apps → LiMP VPN → Battery → "Unrestricted".
6. Sync the clock. Settings → General management → Date and time → enable "Automatic date and time". An incorrect clock breaks the VPN TLS handshake.
7. Update or reinstall the app. Google Play → LiMP VPN → Update. If that does not help, delete and reinstall.

iPhone iOS (7 Steps)

1. Check your base connection. Disable VPN, open Safari. If websites do not load — the problem is not VPN.
2. Disable iCloud Private Relay. Settings → [your name] → iCloud → Private Relay → turn off. It conflicts with most VPN apps.
3. Delete old VPN profiles. Settings → General → VPN & Device Management → VPN configurations → delete all except the one you need.
4. Switch the protocol. In LiMP VPN, open settings → Protocol → try WireGuard, then IKEv2.
5. Reset network settings. Settings → General → Transfer or Reset iPhone → Reset → Reset Network Settings. Note: saved Wi-Fi passwords will be erased.
6. Update iOS and the app. Settings → General → Software Update. App Store → LiMP VPN → Update.
7. Reinstall the app. Delete LiMP VPN, reinstall from the App Store. This restores the Network Extension system permissions.

All LiMP VPN features, including supported protocols and kill switch, are described on the LiMP VPN features page. Plans are on the pricing page.

When to Contact Support

If all steps are done and VPN still does not work — the issue may be on the server side, not your device. Signs of a server-side problem:

• VPN does not work on multiple devices with the same account simultaneously.
• No server works, even though at least one was stable before.
• The app shows "server unavailable" or "authentication failed" with unchanged credentials.
• The problem started simultaneously for other users (check the service status page or community forums).

If only one specific server is unavailable — simply switch to another. If all servers are down — contact support with a description of the symptom, your device, and the protocols you tried.

Verify that VPN is working correctly after reconnecting: how to check that VPN is working.

Frequently Asked Questions

Why is VPN not working on my phone?

The most common causes: an outdated app, the wrong protocol (try WireGuard), battery optimization that closes the VPN process in the background, or a conflict with Private DNS. Restart the app, switch the protocol, and remove battery restrictions — this solves most cases.

VPN connects but internet does not work — what should I do?

The likely cause is the kill switch firing (it blocks traffic when the tunnel drops), a DNS leak, or an incorrect MTU. Try disabling kill switch in VPN app settings, changing the DNS server, or reducing MTU to 1300 bytes.

How does battery optimization interfere with VPN on Android?

Android restricts background activity to save battery. If the VPN app is subject to restrictions, the system terminates it in the background and the tunnel drops. Fix: Settings → Apps → [VPN app] → Battery → select "Unrestricted" or "Allow background activity".

Why does VPN on iPhone fail to connect after an iOS update?

After an iOS update the old VPN profile can become incompatible. Delete the profile in Settings → General → VPN & Device Management, then re-add your subscription in the app. Also check whether iCloud Private Relay is enabled — it conflicts with many VPN apps.

VPN works on Wi-Fi but not on mobile data — why?

Mobile carriers and Wi-Fi networks can process traffic differently. If VPN only works on Wi-Fi, try switching the protocol from OpenVPN (UDP/TCP) to WireGuard or IKEv2 — they are more compatible with mobile networks. More detail in the article on VPN not working on mobile data.