iPhone disconnects from Wi-Fi when locked since iOS 27 – how to fix?
Since updating from iOS 26 to iOS 27 (still happening on 27.0.1), my iPhone Air disconnects from Wi-Fi a few minutes after the screen is locked.
When I unlock it, the Wi-Fi icon is still shown, but there is no internet and the iPhone does not reconnect by itself. My access point logs confirm the iPhone was disconnected while locked. Only turning Wi-Fi off and on again restores the connection.
This happens on different Wi-Fi networks. All other devices on my network, including a Mac, Apple TV and HomePod, stay connected without any issues. Signal strength is excellent. On iOS 26 everything worked fine.
Already tried without success: restart, reset network settings, disabled Private Wi-Fi Address and Connection Assist, removed all VPN profiles, tested a static IP. Apple Diagnostics found no issues.
Is this a known issue with iOS 27? Has anyone found a fix or workaround?
iPhone Air