User & Password window

When I’m trying to enter the user and the password, I’m getting the error from the title, how i can fix that problem?, my teacher want me to use this method for logging with multiple users and passwords without making more ‘MySQL Connections‘, but i can’t find any clue for how to do it, the only way that i find for do it is via making multiple ‘MySQL Connections‘ and enter the User there, but my teacher don’t want that… thanks for the help!!!

I try everything that i find in internet and i can’t find anyway to make it work, idk if that thing is possible or if my teacher is just trolling us