Your bank can also tell you if your card is not approved for online, international, or recurring transactions.
In the Office 365 admin center, you can add a new credit card, update an existing card, or delete a card that you no longer use.
You can also change the card that you're using to pay for a subscription.
If you continue to see the "declined" message, contact your bank.
It’s possible that your card isn’t active—for example, if you recently received the card in the mail with an updated expiration date, you may still need to activate it.
Note: If you’re using Office 365 operated by 21Vianet in China, please contact the 21Vianet support team.