MySQL user does not work after disable/re-enable virtual server in virtualmin

When I disable and re-enable a virtualserver the MySQL user refuses to work afterwards. I managed to get it working by using a MySQL query: alter user 'user'@'localhost identified by 'password';. So I suspect something goes wrong with re-enabling the password.

Details about my server:

• Ubuntu 18.04 LTS
• MySQL 5.7 (default for 18.04 release)
• Installed through install.sh script. The only thing I've changed from the base configuration are setting the server to php-fpm handler.