All bands tend to move as your baby grows and there are more wiggles. But there are ways to keep it from sliding. Wear the band underneath a bodysuit, this will help keep it in place and is closest to the skin, which allows it to do it's magic by heating using your baby's body temperature. If you want to place it over a bodysuit, we recommend making it a bit tighter than you would if you put it on underneath. This helps the velcro to catch and keep it in place better. If the band is too loose, and there is no tension, the band will move. The  soft velcro is used as a safety factor for the baby. Also, do not wear over outer clothes or pajamas.