Toubleshoot SMS Deliveries Faliures

First, let's check your SMS logs:

1. Navigate to your dashboard (Developer -> SMS -> SMS logs)

2. Search using the recipient's phone number to find specific messages, or look for any sending/delivery failures if you're investigating multiple cases

Once you find your SMS in the logs, here's what different error codes mean and how to fix them:

* Your recipient has chosen to opt out or unsubscribe from receiving messages

* The fix: Head over to your suppression settings page to review and manage your opt-out list

* You're trying to send messages to a number that can't receive them (like a landline)

* The fix: Update your contact list to remove these numbers and prevent future attempts

* Your channel doesn't have permission to send messages to this location, usually due to country restrictions

* The fix: Check the regulations for your target country here and if everything looks correct, reach out to support to verify coverage remember to provide them few samples including a timespat a receiving number and the originator (from”) the message was sent

* The number you're trying to reach isn't active anymore

* The fix: Remove these numbers from your list - even if they become active again, they'll likely belong to different people

* The recipient can't be reached right now (their phone might be off or they're in a no-coverage area)

* The fix: Try sending again later, but avoid multiple immediate attempts

* Your messages have been blocked because of your sending patterns or message content

* The fix: Review the policies for your target country here and adjust your approach - you might need to slow down your sending rate or revise your message content

* Sometimes the telecom network doesn't tell us exactly what went wrong

* The fix: Gather several examples and contact our support team - we'll work with the carrier to investigate

Error: DestinationBlocked (HTTP 422)

Cause: Your workspace has an allowed destinations list that controls which countries can receive SMS. The recipient's country is either not on that list or has been explicitly removed. This list exists to help you prevent accidental or unauthorized messaging to countries you don't operate in, and to limit exposure to high-fraud or high-cost destinations.

What happens: The error is returned synchronously — the API rejects the request before any message is created, queued, or attempted. No credits are consumed and no status webhooks are fired.

Fix: Add the destination country to your allowed list. Changes take effect within 1 minute.

This means your SMS never made it into our system. Check these places:

* If you sent via API: Look for rejection messages in your API call details

* If you used Flow or Journey: Check those specific logs

* If it was part of a campaign: Review your campaign failure list

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