Is there a repair method if you don’t have a fstab backup?
can i take the files from someone else and just overwrite mine if the install is standard dietpi on my rbpi3 with xfce? 
Is it maybe related to this topic:
Dietpi Services not starting
https://dietpi.com/forum/t/dietpi-services-not-starting/2966/1
cat /etc/debian_version
returns debian 9.6