The problem with the speakers

When connecting speakers to a PC one of the speakers is not working. I changed the column order and the one that was not working started working but the one that worked stopped working forgot to mention that the speakers connect to the subwoofer, and through it already to PC. I tried to connect to the speakers via Bluetooth and they both worked fine. I decided to connect the speakers to the phone via cable, and again, one did not work. I can't understand what the problem is in the adapter from the subwoofer to the PC or the subwoofer.