If you enter your six-digit 2FA code correctly within the 30-second time limit and still encounter a “2FA Google Auth is invalid” error, it could be that your 2FA application is not properly synchronized with your device's time zone settings or the network time.
*** To fix this, enable network syncing under Date & Time settings on your device.
Go to System > General Management > Date & Time
Switch on "Automatic date and time"
Go to Settings > General > Date & Time and switch on "Set Automatically"
*** If the error persists, we recommend you to delete your 2FA entry and create a new entry using the QR code or the manual key.
*** If still didn't work you may have to disable your 2FA for the mean time. Please check this link for your reference.
For questions and inquiries, please feel free to contact us.
BITKUB ONLINE Co., Ltd.
Telephone: +66 2-032-9555