Yes, a lot of people have faced issues using Mercury cards to pay for Facebook (Meta) Ads—it’s pretty common.
Mercury cards are commercial debit cards, and Meta tends to prefer credit cards (Visa, MasterCard, Amex) over debit cards for ad payments.
Meta’s fraud detection system sometimes flags fintech-issued or "virtual" cards as higher risk, even if there’s no actual problem.
Mercury’s payment system may block international/advertising transactions by default for security reasons unless you enable certain settings.
How to Fix It:
1) Contact Mercury Support
Ask them to whitelist Facebook/Meta transactions for your card.
Also, confirm that international transactions and online advertising payments are enabled.
2) Add a Backup Payment Method
Add a second real credit card (if possible) to your Business Manager. This keeps your campaigns running in case Mercury gets declined again.
3) Try Using PayPal Linked to Mercury
Add your Mercury card to a PayPal account and then pay Meta through PayPal.
(PayPal sometimes bypasses strict card verification.)
4) Use a Different Card for Ads
If issues persist, it might be faster to use a different bank card specifically for ad payments (traditional banks tend to have fewer problems).