回複：How to get my money back

Do you have proof, like copy of a check? If so you can probably bring this to a court. You may need to spend some time dealing with the paperwork. This may or may not worth it, depends how much money you can make each hour if you spend your time otherwise.

Doing this with a lawyer may not be a good idea, since I guess the lawyer will cost more than that, or no lawyer will even be willing to handle the case.