My Elecfreaks Retro Arcade (the non-micro:bit one) won't enter pairing mode despite having followed every direction exactly.

I already have a different game loaded onto it, which could be the problem, but I’m not sure if it is. Grant you, the thing was left untouched for several months, but I even unscrewed the thing and looked inside. Everything seemed fine. If anyone knows how to fix this, please tell me.