I am still having this same issue with my Model Y even on 2020.40.3. I.e. my Tesla Mobile Charger works, but my EnelX Juicebox, which had worked for 9 months, now just never starts charging and after a few seconds stops trying to send current. Tesla service tells me to call an electrician, but after reading a few others' experience here, I am (1) crossing fingers that 2020.40.4 will fix this, or (2) hoping that a service technician can diagnose this in-person as a possible PCS issue, but I have a feeling they are going to cancel my appointment.