If you received this billing notification, it was because we were not able to process payment on your account.  There are several different reasons that your card could have been declined.  To get this issue resolved, please log in and update your payment information and resubmit for payment here:

https://sendgrid.com/billing/automaticPayments

For additional information on getting your card updated, please review our billing tips article:

http://support.sendgrid.com/entries/21289478-billing-tips-how-to-up...