According to your description, the company violated the labor law. First of all, you can find Taian Labor Arbitration Committee to solve it. If you can't handle it or are not satisfied with the result, you can sue. This is a matter of procedure. If you don't understand this procedure, you can consult a lawyer. There are many law firms in Taian.
My husband is studying law. Although he is not in this field, I also know some laws and regulations. I will always pay attention to them. I wish you a satisfactory answer. You are also welcome to visit/. A "Law Online" column has just been opened here, and we are going to hire some legal experts to analyze legal issues for you.