Fusion Studio 8.1.1 No Dongle found ?

I installed Fu8 on two PC, it works after Installation, but after some days I could put the Dongle in and Fu8 give me a No Dongle found. I tried different USB-Ports but no change.
https://forum.blackmagicdesign.com/
https://forum.blackmagicdesign.com/viewtopic.php?f=22&t=49818