If this unit is still under warranty, Baumatic will repair it for free. Their service number is 0118 933 6911. I recommend trying them first before making any repair attempts. You could try unplugging it for a couple minutes to reset the computer.
Hi, to remove the glass there is a plastic sealing section at the top of the oven door with 4 slots in, use a coin placed horizontally into a slot and turn clockwise until you feel the seal disengage then repeat on the next 3, then you will be able to remove the plastic sealing section and access the door glass that can simply slide out one at a time.
