Well, I found out from the SWSoft foruns that there is a bug in the Plesk Migration manager:
it seems that the auto_increment property of the MySQL tables aren’t being set. I didn’t experience this in the 8.1.1 -> 8.2.1 move. Only now, with a migration from 8.2.1 -> 8.2.1.
Well, the problem is how can i fix this in the MySQL database?
Don’t really know much about MySQL so any help will be apreciated. Thanks in advance.