You can edit, remove or add payment methods on Facebook
If you need help in finding your Facebook Payment info, just follow the steps below;
1) log in to your Facebook account
2) click the small arrow on top right corner of the page (on the dark blue background)
3) choose Settings from the drop-down menu
4) click Payments on the left column of the page
5) click the headline Account Settings
Under the headline 'Payment Methods' you see your Mastercard and choices 'Edit' and 'Remove'. Click 'Edit' to update your credit card.