Failure logging into mysql server

I’m having an issue with getting NC installed. I’m running the official docker image and a separate mariadb container. I’ve set my username and password as well as the host and database to use. I’ve already created the user as well as the database. I’ve also tested the username and password by logging into the mysql server remotely. The user has all privileges to the database.

When I go to create my first NC user and finish the install, it says that my username and password are invalid. Upon further inspection, config.php appears to have a salted password. Every time the login page loads, it changes the string again.

What’s going on and why can’t I get logged into the mysql server?