Oven not heating correctly whirlpool rf362lxtt

Oven/Range/Cooktop Repair
1

Brand:WHIRLPOOL
Model Number:RF362LXTT
Main Symptom:OVEN NOT HEATING TO SET TEMP OR MAINTAINING IT
What happens & when:PREHEATS LIKE NORMAL BUT DOESNT GET TO SET TEMP THEN COOLS DOWN TO 250

Error Code (if any):NONE
Parts or tests already tried:
Photos / video link:

2

Try this: turn the broil element on, does it get red hot? Then, turn the bake element on. Does it turn red? If they both turn red, replace the main control. If one of them does not turn red, replace that element.