First you must find out the clause of the quality problems and furnish sufficient evidence.
首先你的查查有关质量问题的条款,并提供足够的证据。
Any kind of backing out of the contract will be charged a penalty as has been stated in the penalty clause.
任何背弃合同的行为将受到惩罚,这已在处罚条款里写得很清楚了。