How to remove a Google account that keeps on reappearing in MacOS?

Dear all,

I have a google account that does not stay 'deleted' from my iMac. When I remove (and delete from all other devices) the account from 'internet accounts' it reappears after a minute and adds itself to my accounts list. I've never used the account on my iMac only in Safari (private browsing) and never on any other device; password is not stored in the keychain.

This problem drives me nuts and I can't figure out how to keep google away from my system.

Thanks!