First of all, you should make the following points clear: 1) Is the defective rate of this product the same in each batch or concentrated in several batches; 2) Whether there are relevant size requirements in the previous finishing process can confirm the material grade; 3) During the period of this problem, the countermeasures for this problem are different in mass production and trial production, and the hardware aspects are mainly considered in trial production, such as mold matching, cavity accuracy, product positioning accuracy, etc. Mass production can consider the influence of the change point of 4M 1E on the product; 4) Observe whether there are any changes in other dimensions, and whether there will be the problem of insufficient plastic compression mentioned by the landlord. Have you considered it? Otherwise, I don't know your specific information, I can only provide ideas.