Template Undeliverable Error When Sending from Cloud API to a CoEx Number

What is this error?

If you are sending a template message from a number that is onboarded on the Cloud API to a recipient number that is onboarded on CoExistence (CoEx), you may see an error message that reads "Template Undeliverable." This can be confusing because the error appears to indicate a failed delivery.

What actually happens?

Despite the error message, the template is successfully sent and delivered to the recipient at the backend. The recipient receives the message without any issue. Additionally, the cost for the template message is deducted from your account as expected, since the delivery did take place.

The "Template Undeliverable" error is a display-level issue on the sender's end only. It does not reflect the actual delivery status of the message.

Why does this happen?

This is a known limitation that occurs specifically when there is a mismatch between the infrastructure types of the sender and the recipient — Cloud API on one end and CoExistence on the other. The delivery confirmation that would typically mark the message as "sent" does not return correctly in this scenario, causing the system to show an undeliverable error even though the message has gone through.

What should you do?

If you encounter this error while sending a template to a CoEx number, you do not need to resend the message. The recipient has already received it, and the charge has been applied. Sending the message again will result in a duplicate delivery and an additional deduction.

This is a known issue and is currently being tracked. If you are regularly sending templates to CoEx numbers and are seeing this error frequently, you can reach out to the support team for further assistance.