Whirlpool microwave control panel - some buttons not working

(Whirlpool model no. W10835580A). Recently four buttons on the control pad stopped working: "cook power," "defrost," "4," and "9." I don't know whether they all stopped working at the same time, as we rarely use those buttons...therefore I think it's a wiring issue and not a case of some buttons "wearing out," if that makes sense. I tried unplugging/rebooting. Not sure if I need a new touchpad or...?