回複：what is the form about?

Sorry, I forgot the name of the form. You can call them to ask for the procedure to appeal. I did the same thing at that time (it was about 6 years ago.). Remember, the amount of the money you brought is not illeagal. The problem is you did not declare truthfully, so you are under suspection of illegal money smuggling. Basically, they require you to prove the money is clean. You may be fined for a small amount. So, prepare your documents (income record, bank deposit record, written testimony from others...) as soon as possible. It takes time for you to obtain these things in China and send them back to you.