There is a typo in the entrypoint.sh script for both Apache and Nginx docker images used before OpenPanel 0.2.3, which caused the MySQL service in user containers not to auto-start on server reboot.
This issue will be automatically fixed in the upcoming 0.2.4 update, which will be released ahead of schedule to address this critical bug.
If you do not want to wait for the update:
Update images used for new accounts:
docker pull openpanel/apache && docker pull openpanel/nginx
Update for all existing users:
for username in $(opencli user-list --json | awk -F'"' '/username/ {print $4}'); do docker exec $username bash -c "sed -i 's/MYSQ_STATUS/MYSQL_STATUS/g' /etc/entrypoint.sh"; done