first off, try checking that pigtail attaching to EVSE is firmly plugged in, try unplugging and plugging pigtail back into the evse. Next step is try the 120v to see if it triggers a fault. Have you been using this nema 14-50 outlet for some time? If it's new it could be a fault with the outlet. This is possibly a failed portable EVSE, these are covered under the vehicle warranty.