A battery tender might be the culprit. The F56 SE’s 12V battery is topped up by the HV battery, so if a failed tender created a heavy load, the HV pack could have drained in under an hour. The car’s software prevents internal systems from fully discharging it, but it can’t stop an external device. A fully dead 12V battery also bricks the car. Try using a proper charge pack on the 12V, then once the car responds, plug it into a 220V charger and restore the HV battery to 50%.
