KitchenAid KESC307 Electric Kitchen Range "set probe temp aid" Questions

set the bake temp at 450 and after 50 mins, the temp is only 388. Cut the power to the stove twice, with same results. Using a digital Accu-Rite digital probe on center rack. I have read that there is

...repair would be the oven control. If a service person does change the oven control... "make sure" they use a temp probe to verify the oven control setting and the actual oven temp are the