In general, most of the carton problems occur in this situation, you can first fold the carton manually, without using any external force, to see whether the top cover of the carton is aligned, if the carton cover is staggered and a part of the carton has been extended outside the carton box, which is not right, this situation will cause the carton warping. There is also a case that the upper movement is too tight, forcing the carton to bear greater tape resistance, but this situation rarely occurs, even if there is, it is only very slight warping, will not be very obvious, and will not affect the appearance of the situation.