what to do with the wrong apple charger

Ihad gone to the genius bar to see what was wrong with my charger, (it works one day then, not the other) i got everything checked and nothing was wrong. So i recieved everything that was mine back. I arrived home to realize that i had swaped chargers. (mine 60W and recieved 85W). I am not sure what i a supposed to do in this case.