SMS not sending

Diagnose SMS consent, phone verification, credits, provider, and opt-out problems.

6 min readUpdated July 2026

Check these areas

  • Phone & SMS connection
  • Assigned sending number
  • Recipient mobile verification
  • STOP opt-out or do-not-contact
  • Marketing consent
  • Credits
  • SMS queue and delivery logs
Video walkthrough placeholder showing SMS error, Phone & SMS integration, opt-out warning, SMS queue, and delivery log.
Video: SMS not sending
Video walkthrough placeholder showing SMS error, Phone & SMS integration, opt-out warning, SMS queue, and delivery log.
SMS send error showing recipient phone, opt-out status, consent warning, credits warning, and delivery log link.
SMS send error showing recipient phone, opt-out status, consent warning, credits warning, and delivery log link.

Fast fixes

  • Verify the phone number
  • Use a different eligible recipient for testing
  • Top up credits
  • Reconnect Phone & SMS
  • Do not override STOP without documented consent

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