Gem Car won't go!

I have a GEM 2008 E4 and I have been very happy with it. But today when I unplugged it the indicator light still shows that it is plugged and when I release the parking brake the buzzer sounds and the car will not move.

This past winter when the temp was in the 50s it would take the car 30 seconds or so to recognize that it had been unplugged but this time it seems to be stuck and thinks it is still plugged in.