After deleting customer groups in viruemart 2, access to the joomla 2.5 admin panel was lost. How to get access back?

Question

CMS

Hello, I recently climbed viruemart and came across groups of buyers, they seemed unnecessary to me and I deleted them, then I flew out of the admin panel and could no longer get into it. Went to phpMyAdmin for a solution. I checked the access rights, just in case I created a new user and gave him 8 rights, I still couldn’t log in. Then I decided, following the instructions from the Internet, to create another user with Grant rights, this did not work out for me due to limited rights. Got the following errors:
#1045 - Access denied for user 'vh179543_lois'@'localhost' (password used: YES) (for this request: GRANT ALL PRIVILEGES ON * . * TO 'Super User'@'localhost'
#1227 - Access denied. You need CREATE USER privileges for this operation (for this: CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password'
Google, someone solved a similar problem by simply setting permissions for a new user, but it doesn't work for me. Maybe I indicated the wrong username for setting the grant (although I tried both what goes in the error and how the user is named in the database). The host in the config is registered as a localhost. Maybe I got into the wrong jungle at all. mysql> -u root doesn't work, it just doesn't read the syntax, any help would be welcome.