Tesla Motors Club

I have a 90d and I set my charging to 90%. It's a March 17 build and my 90% is 236 miles. For the last few days, the car has been parked in the garage but connected to the charger. It's dropped from 236 miles to 225 and I'm curious when the car will automatically charge again to get back to 90%?

Is there a certain percentage it needs to drop before it charges? Do I need to unplug it and plug it back in?

Thanks