GMAIL says error and requires signin everytime since mojave upgrade

I upgraded to Mojave, now gmail requires password user/every time and profile says error in red. It says Sync isn’t working. All was well before mojave upgrade. Anyone else with this issue? All help appreciated…


I don’t usually use Safari on the Mac to access Google stuff, but when I just tried to log in to Gmail I was asked to confirm my identity, and was asked if my phone was handy. I clicked Yes and on the Mac screen appeared a 2-digit number inside a circle and on my iPhone an alert (which didn’t look iOS-like) from Google asked if I was trying to log into my account.

I clicked yes and was shown three 2-digit numbers and had to tap on the correct one. The instant I did so I got access to my Gmail.