Too add or update your credit card for your software subscriptions, open https://shop.opendoorerp.com:
Login in to your account and select "My Account"
Select Credit Cards and either add a new card or edit the existing.
Please note, you can not delete a card that has historical transactions. Please advise your account manager to assist and we can deactivate cards you do not wish to use any longer internally to remove them from your list.