I didn't sign an agreement with them, did I? If there is a refund, you have to deduct a certain fee. As long as you don't quote too much, forget it and feed it to the dog.

If you really think they have breached the contract or you have more classes, you can call the industrial and commercial department for arbitration.

PS: Don't go to that place for classes in the future. Just a bunch of liars. They are quite rogue in dealing with students' dissatisfaction or refund of fees. The so-called teachers they recruit are all normal students who have just graduated or haven't graduated. You can find one privately, which is many times cheaper.