Password change -- Problems in Mail app
I just upgraded to Monterey 12.2 OS. When logging into a regular news site I got a new message saying my password might have been comrpromised in a data leak. I changed my Google password (which is what I use) in all 3 devices I use -- iMac, iPad, iPhone. The iPhone and iPad are fine. But on iMac with this new OS, my Mail app does not now recognize my mail (messages stay in Outbox, unsent). When I go to accounts and select Google, it asks me to grant MacOS permission to read and delete all my emails, contacts (what terrible language --- why would I want that? I think the message meant 'do we have permission to do in the app everything you do on Google?'
When I said yes, then I get a message simply saying 'this account already exists' --- which makes no sense at all. I cannot send messages (or receive them) on my Mail app on iMac. How do I solve this? Thanks.
iMac 21.5″, macOS 10.15