Can you describe current status and provide some more details?
systemctl | grep mariadb
systemctl | grep mysqld
systemctl status -l rh-mariadb105-mariadb@nextcloud.service
/opt/rh/rh-mariadb105/root/bin/mysqlshow --socket="/var/run/rh-mariadb105-mariadb/nextcloud-mysql.sock"
mysqlshow
/opt/rh/rh-mariadb105/root/bin/mysql --socket="/var/run/rh-mariadb105-mariadb/nextcloud-mysql.sock" -e 'SELECT user FROM mysql.user'
mysql -e 'SELECT user FROM mysql.user'
grep \'db /usr/share/nextcloud/config/config.php |grep -v dbpass
occ status