Hmm it's definitely something to see if the @Pimax-Support @PM_Sean can arrange a Skype with Teamviewer. Have you submitted a Ticket?
The reason I suggested minimizing the number of devices to keyboard/mouse is that we had a user discover his old Razer Gaming keyboard went funky & caused the headset not to detect correctly.
Have you compared your system with the one that worked to see what's different? Or recall what was installed hardware/software before it stopped working?
There is a setting in the Steamvrsettings file to ensble multiple headsets as well.
But truthfully I think a teamviewer session might be the best action at this time.
@3D_FAN has a good suggestion as well; try setting up another user in Windows & see if the clean user profile works.
Also check your antivirus quarrantine. I use just Windows defender. As part of the software might be being blocked.