Oven does not heat

We have a viking dual fuel 48´´ range that was installed when we bought the house. The appliance is about 2 years old.

The day before yesterday my wife could not not use the large oven. The small works fine.

None of the 3 resistors are working, the fan and the light are ok. I looked for a temperature safety switch and found one in the back panel that when shunt does not change the situation.

Any suggestion would be more than appreciated.

Thanks in advance.

Vince