good news to start.
do you have root access via ssh now?
what do the MariaDB log files say when it tries to start up?
is the MariaDB log file have today's timestamp on it?
your ssl cert is issued by Let's Encrypt.
in a terminal over ssh, type
letsencrypt renew &> /etc/letsencrypt/le_renewal_results.txt
that will attempt to renew the certif and write the results of the attempt to that text file, so if you have problems, you can copy & paste the results of that txt file for troubleshooting