Please follow the below steps:
1. Once your phone is successfully connected to WiFi, stay within reasonable distance of the WiFi to avoid automatic disconnection caused by weak network signal.
2. Ensure not too many devices are connected to the same WiFi and overloading the network.
3. If using a metal protective case, remove it and try again.
4. Please turn the WiFi off and on again.
5. Switch to a different WiFi network.
If the issue persists, contact the Nothing Support Team for further assistance.