Well, it happend to me the other day. The panel cannot be found at all. I cannot remove it or re-add it. If I click remove sensorpanel, it does not remove. Still says "remove sensor panel" after I clicked it.
Btw, what is this reset sensor panel button you are talking about? Is that the remove sensorpanel button that doesn't work?
In 3 years this has not been resolved? 😮
EDIT-1:
Nevermind, I found the resetbutton... However, it did nothing clicking on it... 🤷♂️
EDIT-2:
After reading that there is a new version (7.3) and my version couldn't find any new versions I decided to uninstall completely. The boot file and one more file refused to be removed so, I rebooted and removed them manually. Then, I installed the new version. My Sensor panel is back, however, I have to remake it from scratch to the way I had it. 😵