Going mad with errors

Guys, I need help.

Yesterday I could not access my dolibarr which I have on a webhosting account.

I got a databese error (between is removed for privacy) :

What MAY have happened is that I deleted THE database for this dolibarr and now try to connect with a DIFFERENT copy of the same database on the same server, but accessible through a different overview.

I tried to upgrade from 8.0.2 to 8.0.3 with a copy of the files and the database but after going trough the upgrade process I can now no longer login with the user and password combination. When I try to retrieve my password I get the message that “user” does not have an email address.
I looked in the database and there is one.

Hello,
In the database manager, you have to say that the user has credentials to access the specific database.