help -cooker cuts out

please can anyone help me – i have a diplomat fitted oven (mfi) which is barely 2 years old. The oven will light but after a little while goes off and tries to relight (clicks) this can be fixed by opening the door a little.
Worst still it completely cuts out ie: electrics and gas, after about 40 mins
but the power comes back on again after it cools down abit. i have read on this site about element failyers but i think it may be something else. can anyone help as im willing to have a got at repairs or is it time to replace?

thanks ❓