When you run the first command, you have to wait until Docker actually creates the container:
docker container stop devkinsta_db && docker run --name devkinsta_reset_mariadb_root -v devkinsta_db_data:/var/lib/mysql/ -d mariadb:10.5.5 mysqld --skip-grant-tables
It can take a few seconds. If it successfully creates it, this command should return a basic log:
docker container logs devkinsta_reset_mariadb_root
Again, if you aren’t installing DevKinsta as the administrator, you’ll run into more issues.