Solaar Pair Touble

Hello, I have a Logitech MK850 set which actually worked well. The mouse was causing problems, so I found Solaar and it works. Unfortunately, I once clicked on unpair and since then the mouse cannot be used via USB. The search for new devices is ended with "Device Block". I have deleted the configuration, I have deleted the UDEV rules, but the mouse still no longer works via USB. Does anyone have any ideas what I could do? Thanks Silvio