Bluetooth of mouse not working

Good day all!
I have an issue with the mouse of my son - Razer Basilisk v3 X Hyperspeed. Unfortunately he lost the dongle at the highscool, we tried to connect via bluetooth, but it doesn't work. At the store they also confirmet it doesn't connect as well. As it is in guarantee, theyve sent it for service, but from the authorised Razer service denied to honour the guarantee, as they can't connect it for testing :-)
Is there a way to help me with the situation?