Symptom

When attempting to send multiple SMS in a single API request, you receive an error message that reads, "Error 1: You have exceeded the submission capacity allowed on this account, please back-off and retry."

Applies To

• Outbound SMS

Resolution

If you need to send out SMS in one batch, you will have to keep the connection alive and reuse the API request for each of the destination numbers. Make sure to keep your connection alive so you can reuse the HTTP socket when sending requests and taking full advantage of your account throughput (30 SMS/second).

The best-practice is to leverage HTTP 1/1 and Keep-Alive the connection so each time you are sending a new request you don't need to open another HTTP connection.

Cause

Vonage SMS API can only accept one message per request.

Additional Information

For more information, see our developer documentation for Sending SMS with the SMS API.