Can't Sync Gmail Mail/Contacts – Toggles Turn Off Automatically After Login

Hi everyone,

I’m having trouble syncing my Gmail account with my iPhone. Initially, I noticed that Mail and Contacts weren't syncing. I removed the Gmail account and added it back, but that didn’t fix the issue — in fact, it made things worse.

Now, when I go to Settings > Mail > Accounts > Gmail, I can't enable Mail, Contacts, Calendar, or Notes. Each time I try to toggle one on, it asks me to sign in. After signing in successfully, it briefly shows the toggle as enabled, but once I go back or close the settings, it automatically switches off again.

Has anyone else faced this? Any suggestions on how to fix it?

Thanks in advance!