No idea, manual says it’s a “critical fault”.
Brief google reveals that it’s not a rare occurrence, but the reasons for it aren’t always the same. For example, for some reason the car wouldn’t start charging if it wasn’t locked/in “sleep” mode.
Do you get the white courtesy light when you open the flap? Sorry that i can’t be of more help, just trying to google around.
edit: smartest thing to do probably would be to drive to a public charger and see if it charges there. If it does, something’s wrong with your circuit/connection/cable – if it doesn’t, something’s wrong with the car. Easier to figure out what’s wrong once you eliminate possibilities.
Prior: SEAT Ateca Xcellence Lux 1.5 TSI DSG MY19, VW Golf GTE PHEV DSG MY23
Current: Hyundai Ioniq 6 Ultimate
Next: we'll see what's available in 2028.