So ignoring that line which would need some clarification for me to understand, here’s one answer:
Reading the last sentence sounds like Activate downloaded upgrade sometimes fail which is a bug involving Activate on Windows Service installations. As you see there, a fix was actually attempted, however it made things worse and was retracted until someone could understand the area better…
For now (unless something has changed – I don’t run Service now), restarting the Windows Service would be the solution for Activate not activating. Of course, restarting the computer should work too.
EDIT:
One reason I’m here is I’m wondering if you’re affected by the national blocking of Duplicati updater.
Release: 2.0.4.37 (canary) 2019-12-12 discussed that, and there is a partial solution, for the notifier.
Releases announces releases. For installs you can try https://github.com/duplicati/duplicati/releases
Duplicati freezes on file deletion process says you’re on 2.0.4.28_canary_2019-09-05 as seen here, where you’re keeping up with Canary very well. I wasn’t sure how you got behind four months ago…