How to fix PE fault for feyree 3.5KW ev charger

How to deal with " PE fault " ？ PE fault shows on the screen , it means the ground wire error , our factory set is closed the charger ground wire , but you might reopen the ground wire set by inadvertent ， if you do not connect the ground wire when it is open , it will shows PE "fault " , so you just need to close the ground wire ; so how to close it , please notice " long press A button 10 seconds , you can turn on / turn of ground wire ;