There are several possible reasons why your two-step verification code might not work.
1. Time not in sync in the Google Authenticator app
Try to synchronize the time
Open the main menu in the Google Authenticator app
Select Settings
Press Time Correction for codes
Choose Syncronise
Attention ! The app requires that automatic time synchronization on the device is turned on.
If you are using an Iphone, then make sure that the time on the telephone is synchronized with world time (UTC)
2. Invalid code
It is possible that you previously generated several codes, which may cause one to become invalid.
If these instructions have not helped solve your problem, you can always disable two-step authentication by contacting support by following the instructions in deactivating 2fa.