Why is my message sent but not delivered?

Sent and delivered mean different things

A sent status means WhatsApp accepted the message; delivered means it reached the recipient’s device. A successful API request by itself does not prove delivery or that the recipient read the message.

Delivery can be delayed when the recipient is offline. Account restrictions or blocking may also affect delivery, but a missing receipt alone cannot identify the cause.

Check the message

1. Use the message-info endpoint with the WasenderApi integer msgId returned when sending to check the latest recorded status.
2. Check your message-status webhook events and confirm that your receiver processes updates for the same message.
3. Send a test to a known active number whose owner expects your message.
4. Open WhatsApp on the sending account and check for warnings. If appropriate, test the same recipient manually to see whether the problem also occurs outside your integration.

Avoid repeatedly resending while a message is pending; it could arrive later and create duplicates.

Read receipts are a separate step

A delivered message may never show a read receipt. See troubleshooting missing read status. If you need support, provide the session ID, outgoing message ID and time of the send.