Hotpoint EG94X bottom oven not hot enough

Hi, I have a Hotpoint EG94X double oven.
The lower large oven only reaches temperature after a very long time, the rear round element does not get hot but there is nothing wrong with it. I purchased a new one which did not fix the error, I then took took the round element to work and a electrician said it was ok too (should have done that first 😕 ). Looked in the back of cooker but nothing seems to be loose or blown to the eye.
Any idea’s would be appreciated, Christmas is just around the corner…8O

Regards, Chuckster66