Thank you for your answer.
But I still don’t know what’s wrong. I tested the USB connection again and it didn’t work. It turned out that I managed to connect via a mobile network.
The network is not loaded and the router is 1 m away from the tablet/smartphone.
Unfortunately, I don’t have a WiFi card on my PC and I can’t use WiFi direct.
The PC connects to the router via cable and the smartphone via WiFi, so far there have been no problems.
Thank you very much for previously sending in all your logs. We can see that spacedesk native USB connection is failing indeed with an unspecified error. It is very strange to see USB Tethering work while our native USB connection does not work. Does this happen on both of your Android devices? On your Redmi Note 8 Pro and your Prestigio MultiPad. Could you maybe also try a different cable? We never had any report of such a problem. If anyone else experiences a similar problem, please also reply to this thread.