The upper cover thermistor is open or short-circuited, just replace the upper cover thermistor.
If the cover is not in place or the trigger switch and its wiring are faulty, the solution is to close the cover normally, and check whether the trigger switch and its wiring are normal, and whether the microswitch contacts can be effectively closed after closing the cover normally.
If all the above aspects are normal, it may be because the pot does not meet the requirements. It is recommended to use the pot that meets the requirements. If the above methods can't solve the problem, it is suggested to restore the rice cooker to the factory settings or reset the program system. If the problem remains unresolved, it is recommended to seek professional technical support.