It doesn’t work in legacy mode either. The “Locked” mode actually seem to point where the problem is:
Since the knob is not highlighted in “Locked” mode I assume that the clickspot accidently got deleted.
Do you happen to have any of the Working Title Mods installed?
Specifically both the old G1000 AND the new G1000 NXi?
If so, delete the G1000 and ONLY use the G1000 Nxi. That should fix the problem.