1. Click on the Earn Tab. 
2. Click Atlas Shopping. 
3. Click the three lines on the top right to access the menu. 
4. Click My Cards.
5. Click the trash can icon to delete a specific card.

NOTE: Atlas Shopping designed to work with United States-issued Mastercard and Visa credit payments only. Debit cards, prepaid cards, and gift cards will not credit in-game rewards.