Troubleshooting

Fix a Failed Message by Provider

TroubleshootingUpdated 2026-10-17

Every failed message shows an error hint with the provider's code. Pick your provider's tab for its common codes.

SMS Suppliers

Open Settings → Custom SMS Suppliers. If a supplier such as seven (+49) lost its Verified chip, use Send Test SMS again. Check the webhook URL and status map if messages show as sent but never delivered.

If You Also Use…

63016: outside the WhatsApp 24-hour window; send a Content template. 21610: the recipient replied STOP; do not message them. 21211: the number is invalid; check its format. 20003: wrong Account SID or Auth Token; reconnect in Settings → Senders & Numbers.

Steps at a glance

  1. Open the Failed MessageClick the error hint on the message.
  2. Check the Provider BadgeSee which provider sent it.
  3. Find the CodeLook up the code under that provider below.
  4. Apply the Fix and ResendFix the cause, then resend.

Frequently asked

Where Do I See the Error Code?

In the error hint on the failed message.

Why Does WhatsApp Fail After 24 Hours?

Outside the 24-hour window only approved templates can be sent.

What If the Code Is Not Listed?

Run Test Messaging, then contact support with the code.

A +49 SMS Through Seven Failed. What Now?

Check seven still shows Verified in Settings → Custom SMS Suppliers and that your routing rule for +49 points to it.

Next step

Apply this to your own deployment

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