electric dryer no power, no light

My dryer has no power, it turns on by knob and it sounds like knob rotates well but no power. Electric outlet tested ok. The repair man diagnosed that it needs new control board, so I ordered the part and replaced it, but still no power. Some people suggested to check if the door close correctly, but mine turns on when the door is open too, so that’s not the case. what could be wrong? or should I buy a new machine… Please help!!