GY6 Rear Tire Locked Up

[RaveningRyan]

I am new to the site although I've been directed here many times from goggle searches. With that said I apologize if didn't search the forum long enough to find a similar thread.

I have a 2009 Chinese GY6 150cc scooter. I bought the scooter off Craigslist and have been troubleshooting problems ever since.

Yesterday I was out for a ride and it was doing fine, however I pulled into the yard and parked the bike and my rear tire locked up. Manually the tire will rotate back and forth about a half inch. If I crank the scooter and apply throttle the tire will turn. I've been searching Google and YouTube for answers only finding results about drum brakes this scooter has disk brakes front and back. I don't know what I need to remove, clean, adjust ect. Any advice would be greatly appreciated.