"Gateway Errors" occur when messages sent from our system encounter issues passing through to our aggregators (ex: The remote server returned an error: (502) Bad Gateway ). 

When this error occurs, please submit a support request that includes the Client ID, mobile recipient, and date / time of the failure. 

Our team will need to verify if the issue occurred due to something happening on our end of the equation and, or, work with our upstream partners to remediate the issue.