I'm using only one antivirus.
I just powered off the machine, took the battery out and opened the case, then I checked the cables connecting to the wireless device (luckily it's the module that is easily accessible in my laptop. After that I closed the case, powered up the PC and the device got recognised.
I think the most probable in this case is that the cables could be slightly loose and moving the computer might cause problems with connection. I'm going to give the laptop to the shop to get it checked properly.
I will mark the thread as "probably solved" for now. I will post an update if the problem occurs again and whether checking the cables helped again.
Thank You for Your help joe_intel!