我再次表示，我愿努力做到少出质量毛病，减少麻烦，稳定地与您合作。翻译一下，谢谢了！

I would like to promise again that I will try my best to avoid making fewer quality problems and causing you any inconvenience, so that we can have the steady cooperations.

Indicated once more that, I am willing diligently to achieve am fewthe quality problem, reduces the trouble, stably cooperates with you

I can tell you again that I will strive to lower the quality problems and reduce the troubles, stably cooperate with you