Diaper exchange

em

So I’ve been seeing on a mom group I’m part of on Facebook that you cane trade an unopened pack of diapers for a new size. Well my sons out of newborn and I have two brand new unopened packs of diapers size newborn and want to trade them for bigger sizes. But they were given to me during the diaper raffle. So the question is has anyone done this and how? I have no idea what store they came from and I’m under the impression they need to be traded at the store of purchase . I’ve texted my mom friends and no one has done it so any advice would be great 🤨