There is too little crotch fabric, which is easy to fall off when you walk. In addition, the hip elasticity is not enough, the trousers can't hold the trousers, and the trousers slide down, resulting in the crotch falling off.

Pay attention to buy tight pants with high spandex (or lycra) content, which are elastic and fit. Also, choose tights suitable for your own brand, and the quantity must be appropriate. If the quantity is small, it will easily fall from the crotch.

Solutions include:

Replace the elastic band, or fold the elastic band for sewing.

According to the specific style, buckles and belts are added.