First of all, take a look at his course and explain whether it has been said. Classes must be arranged within half a month or according to the specific enrollment situation. You can't sue him if there are corresponding provisions, but if he doesn't have these instructions, he can call the consumer hotline 123 15 to make a complaint. Or make a complaint on the official platform of public comment. If it is of little use, you can go to court to prosecute, but it usually takes a long time for the court to prosecute. You can refer to it when you have time.