Keep trying with Mercadopago to reverse the transaction, since it's also a banking entity in every LatAm country it has presence, you can escalate - for example

Keep trying with Mercadopago to reverse the transaction, since it's also a banking entity in every LatAm country it has presence, you can escalate - for example in Chile there's the Consumer Protection from the ABIF (Association of Banks and Financial Institutions) Also do report the fraud to keep a paper trail. Next time get a credit card from an actual bank, even if your country has banking laws protecting you from fraud with prepaid debit cards, the insurance and reporting procedure with credit cards is much more streamlined worldwide.