[clug] systemctl - timer keeps cancelling, I think

[Tony Lewis]

Hello all,

I'm pretty green with systemctl, but muddle my way through.  I'm using 
it to manage my backups.  For one part, it's just not working.

I have a service that uses imapsync to backup emails, and then calls 
borg to push the files into my backup repository.  The timer currently 
shows "n/a" for both NEXT and LEFT, and the timer never fires:

email at host:~$ systemctl --user --all list-timers
NEXT LEFT LAST                         PASSED              UNIT 
                  ACTIVATES
n/a  n/a  Sun 2022-05-08 14:45:52 AEST 4 months 0 days ago 
imapsync-emails.timer imapsync-emails.service

If I manually start the service, it work, and the interesting bit is 
that for a while, the timer shows that it is intending to fire:

email at host:~$ systemctl --user start imapsync-emails
email at host:~$ systemctl --user --all list-timers
NEXT                         LEFT          LAST 
                         PASSED              UNIT 
                  ACTIVATES
Thu 2022-09-08 15:21:33 AEST 1 day 1h left Sun 2022-05-08 14:45:52 AEST 
4 months 0 days ago imapsync-emails.timer imapsync-emails.service

But after a while (not correlated with when the imapsync job finishes), 
it will revert back to "n/a" and not fire.

I've tried disabling and re-enabling the timer and the service, and it 
doesn't appear to help.  The backup job appears to be exiting successfully:

Sep 06 09:19:16 host systemd[133305]: imapsync-emails.service: Succeeded.

Any clues of what I can do?

Tony