Mask tracking not working

[valedit]

Hello,
I've applied a Sharpen fx to my clip and added a mask, but the tracking is not working. I don't get any progress. And after trying, all the buttons are greyed out.
I tried different clips and projects, I cleared the cache, database, started from scratch, restarted Premiere, clips from different HD, tried different fx, tried to track a mask in Opacity…The tracking is not consistently working, sometimes it does, but most of the times it doesn’t.
I’m on Premiere 25.1.0
Any help?
Thank you!

[R Neil Haugen]

This is something where seeing a screengrab of what you're trying to mask would help.

Premiere will need a pretty clean contrast line to 'see' something to latch onto, and that might be the issue.