Symptom:
Mavic Air requests 'DJI GO' App and NOT 'DJI GO 4' on Wi-Fi Connection (see attached screenshot)  This started after a firmware reload of version 01.00.0400 via Assistant 2 .  The app then asks me to confirm that I have a Phantom model.
Attempts to reconnect by various means did not solve the problem.
When connecting via the Wired Connection the app correctly recognised that my drone is a Mavic Air
Solution:
Press the Function Button on rear of the aircraft for 6 seconds until the aircraft beeps 3 times.  (Same process as Wi-Fi password reset)

Hi there, I do apologize for the inconvenience and trouble caused. Could you please try to uninstall and reinstall your app? Thanks.

Natalia,  maybe it was not obvious from my post but I solved the problem.  (By holding down the function button). Why do you suggest I reinstall the app?