Electrolux E20 error code?

My 4 year old electrolux electric oven is showing error code E20, the oven seems to be heating over the temperature its showing, Ive just cooked some pizzas and despite the oven showing its temperature at 200 it seemed a lot hotter and part of the oven near the fan was glowing orange and the pizzas were burning on top!!

The oven then didnt cool down when i had turned the switch off it kept on at the same temp (if not hotter) i had to turn it off at the power source

Turned it back on and the oven restarted fine.

Any help and ideas would be greatly appreciated to help me try and save the call out money and or buying a new oven at christmas time, thanks Paul