The oven does not heat

I have a problem with the oven of my Dionex ASE 350. When I set the equipment to work at a certain temperature, it only heats the top plate, but the oven stays at room temperature, and the system hangs forever waiting for the oven to heat up ( In my case, the oven should be set to 70ºC and it stays at 30º constantly, while the system waits for the oven to heat up to go on to the next step). I have checked that the RTDs are working correctly, that the oven is receiving power, and both checks were correct, so it can be confirmed that the problem is with the oven. Does anyone know what could be the reason why the oven does not heat? Thanks in advance!!!

Equipment: Dionex - ASE 350