TS, when you say fake, you mean it's counterfeit right? If so, you cannot safely return it anyway because it's illegal to send counterfeit products via mail or courier.

That's the reason I used to avoid having to return a counterfeit Samsung MicroSD card. Also because lazy. I got my refund from Shopee and kept the card. The card works, just not ori.

Of course, you'll need to prove that it's counterfeit. I took my card to Samsung to verify that it's not a genuine Samsung card.