Zwift looses connection

I have a tacx Flux2 connected through Bluetooth to a windows 10 PC.
In the middle of a race I lately loose connection.
When I connect the Tacx to my Iphone eveything runs perfect, no connection lost.
When I check my bluetooth setting on the windows PC, I see the device is correctly connected (HR too)
I updated the Bluetooth drivers but that didn’t change anything.
Restarting the PC sometimes solves the problem
This problem is new… it frequently occurs form last week on…
Is this a known problem or what do you suggest?
Thanks a lot