Network/Internet problem after updating IOS 26.1

To fix internet issues after an iOS 26.1 update, try resetting network settings (Settings > General > Transfer / Reset > Reset), force restarting your iPhone, toggling Airplane mode, forgetting / rejoining Wi-Fi networks, or checking for a carrier settings update.

If problems persist, update iOS further or contact your carrier / Apple Support. 

1. Basic Troubleshooting (Wi-Fi & Cellular)

• Toggle Airplane Mode: Turn on for ~30 seconds, then off to refresh connections.
• Restart iPhone: A simple power cycle can resolve glitches.
• Force Restart: (iPhone 16) Quick press Volume Up, Quick press Volume Down, then hold the Side button until the Apple logo appears.
• Check for Carrier Update: Go to Settings > General > About and wait; an update prompt may appear. 

2. Wi-Fi Specific Fixes

• Forget & Rejoin Network: Go to Settings > Wi-Fi, tap the network's (i) icon, select Forget This Network, then reconnect and re-enter the password.
• Check Router: Restart your Wi-Fi router and modem. 

3. Cellular Specific Fixes

• Reinsert SIM Card: Power off, remove, and reinsert your physical SIM (or toggle eSIM line off/on in Cellular settings).
• Manual Carrier Selection: Settings > Cellular > Network Selection (Disable Automatic, wait, then re-enable). 

4. Reset Network Settings (Crucial Step) 

• Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This clears saved Wi-Fi passwords and network configurations but often fixes deep issues. 

5. Advanced Steps

• Check for a newer iOS version (iOS 26.2 or later).
• Contact your carrier or Apple Support for potential network provisioning or hardware checks. 

I hope that helps.

if you have VPN on your phone, iOS 26 hates them even more than iOs 18, try uninstalling them fully.