Change mariadbdump.conf but no mysql backup

Hello,
i have installed urbackup server and some clients.
then i change
nano /usr/local/etc/urbackup/mariadbdump.conf
MARIADB_DUMP_ENABLED=1
and user and password of course
then
systemctl restart urbackupclientbackend

for almost all i see rootfs and urbackup_backup_scripts with sql
but on 1 client i see only rootfs
i check more times but user and password is correct
i read also /var/log/urbackupclient.log
but never trace to mysql/mariadb dump…

what can i do to fix?

thank you in advance

on all client