In fact, all you have to do is buy a piece of 16K paper and print it on both sides. The other party just doesn't want to print it because it wants to make a watch. The simplest suggestion is to paste the wrong place with paper (any paper can be changed). After correcting the mistake, make a new copy. Remember to use 16K. If it is not 16K, it is the paper size of B5. Otherwise, you can directly cut A4 yourself.