Why do some breastfeeding moms still chubby/fat when ideally, they should be losing weight?

Hi, I think, it is because when the woman is breastfeeding, no doubt, body is burning calories in order to make milk but at the same time, the woman is eating more to make that milk and also to keep her own body requirements in place. A hormone, called, prolactin is produced in the body that not only stimulates the production of milk but also suppresses the body's ability to metabolise.