Hi aleks_m,
Thank you for your reply and for providing an update on the status. I was referring to the USB Wireless Receiver provided with the keyboard and mouse combo similar the adapter provided in the link below:
I suggest you to uninstall the Bluetooth device from the Device Manager and restart the system and check if it work properly.
Please send the system Service Tag(including the name on the account and contact details) to me via Private Message, if you could not locate the wireless adapter. I will check the system details and let you know the options available.