I’m not sure what reserved means sorry. You have every right to be upset about $300 I would be too! I’m crossing my fingers for you that she isn’t actually a scammer and you will get your item back. Until you get something back it’s all an assumption. There is still hope… however I looked at her closet and she’s dealing in lots of fake items not just LV so she is likely well versed in the reps based on that a high likelihood she will do the switch out. I’m surprised she opened a case based on her closet to be honest.

Wait til you get the item back but you can certainly report her to poshmark and the local police in her area. $300 is a lot to lose for this item but it’s a huge amount for a posh seller she won’t want to lose her account and following.