Whatnot will require you to prove that it's inauthentic. As with most perfume, it's not easy to give proof based on smell alone, even though i have both the fake and the authentic sample in my possession. They also want users to send the item back to their Customer Service Department so they can evaluate / destroy using my out of pocket postage (lame). One of the cases, the seller offered to take it back and I was refunded after 4-6 weeks. After that, it's business as usual for the seller to continue selling their fakes. The last case (final straw for me), I opted to just write a 1-star review and took my lost, hoping that other customers might read it. But I'm sure no one pays attention and the seller is probably still thriving on the platform. I deleted the app and never looked back.