Is this allowed?!?!

I ordered a present for my best friend on Depop. I already purchased the item and weeks later it wasn’t refunded and wasn’t even shipped yet. I then got a message saying that I should’ve canceled my order because she got a higher bid and decided not to ship it to me and sell it to another person after I had already paid. Since she didn’t refund me immediately it felt like she was trying to steal my lonely lol. I just feel like this isn’t allowed but she said it is so I wanted to ask