# Welcome Message Sequences - API Guide | Developer Documentation

<div id="bkmrk-welcome-message-sequ">## Welcome Message Sequences - API Guide

<div><span>Updated: Nov 17, 2025</span></div><div>When creating Click-to-WhatsApp ads, you can connect a Welcome Message Sequence from your messaging app. A sequence can include text, prefilled message, and FAQs.</div><div>This guide explains how to manage Welcome Message Sequences via the API endpoint.</div><div id="bkmrk-requirements"><div id="bkmrk-requirements-1"><div>### Requirements

</div></div></div><div>Your app must be granted the **whatsapp\_business\_management** permission.</div><div id="bkmrk-change-an-existing-s"><div id="bkmrk-change-an-existing-s-1"><div>### Change an existing sequence

</div></div></div><div><div>A sequence linked to an active ad cannot be deleted.</div></div><div>To update an existing sequence, send a `POST` request to the `WHATSAPP_BUSINESS_ACCOUNT_ID/welcome_message_sequences` endpoint with:</div><span>The `sequence_id` parameter set to the ID of the sequence being updated</span><span>Other parameters, like `name` or `welcome_message_sequence`, that need to be updated.</span><div id="bkmrk-sample-response-3"><div id="bkmrk-sample-response-4"><div>#### Sample response

</div></div></div><div>The response includes a success or error message.</div><div id="bkmrk-delete-a-sequence"><div id="bkmrk-delete-a-sequence-1"><div>### Delete a sequence

</div></div></div><div><div>A sequence linked to an active ad cannot be deleted.</div></div><div>To delete a sequence, send a `DELETE` request to `WHATSAPP_BUSINESS_ACCOUNT_ID/welcome_message_sequences` with the `sequence_id` parameter set to the ID of the sequence you want to delete.</div><div id="bkmrk-marketing-api-experi"><div id="bkmrk-marketing-api-experi-1"><div>### Marketing API experience

</div></div></div><div>After you submit welcome message sequences through the API, use the sequence ID to configure ads through the Marketing API.</div><div>In the ad creative, the sequence ID can be set as follows:</div><div>For more information about messaging ads, refer to [Messaging Ads](https://developers.facebook.com/docs/marketing-api/ad-creative/messaging-ads) in the Marketing API documentation.</div><div id="bkmrk-ads-manager-experien"><div id="bkmrk-ads-manager-experien-1"><div>### Ads Manager experience walk-through

</div></div></div><div>1: In the **Message Template** section of the Ad Creative, select **Partner App**</div><div>![Message Template section showing Partner App option](https://support2.chatarchitect.com/uploads/images/gallery/2026-04/embedded-image-x1gfrmfu.jpeg)</div><span>Click the **Partner app** dropdown and select the appropriate messaging partner app.</span><div>![Partner app dropdown menu selection](https://support2.chatarchitect.com/uploads/images/gallery/2026-04/embedded-image-i4jto8ij.jpeg)</div><div>3: Under **Message sequence**, select the Welcome Message Sequence that you submitted via the API.</div><div>![Message sequence selection dropdown](https://support2.chatarchitect.com/uploads/images/gallery/2026-04/embedded-image-7vzlu3nf.jpeg)</div><span>Preview your message sequence and click **Save**.</span><div>![Message sequence preview with Save button](https://support2.chatarchitect.com/uploads/images/gallery/2026-04/embedded-image-g7fwhkz9.jpeg)</div><div id="bkmrk-error-codes"><div id="bkmrk-error-codes-1"><div>### Error codes

</div></div></div><div><table><thead><tr><th><span>Code </span></th><th><span>Description </span></th><th><span>Possible Solutions </span></th></tr></thead><tbody><tr><td><div><div>`4027001`</div><div>Invalid input data</div></div></td><td><div><div>Some or all of the input data is not of the required format.</div></div></td><td><div><div>Check all the fields and parameters passed into the request are of the correct type and format, and that all required parameters are present.</div></div></td></tr><tr><td><div><div>`4027005`</div><div>Unable to create a welcome message sequence</div></div></td><td><div><div>An error occurred while trying to create a new welcome message sequence.</div></div></td><td><div><div>Check that the access token has all the required permissions for the WhatsApp business account.</div></div></td></tr><tr><td><div><div>`4027006`</div><div>Unable to update a welcome message sequence</div></div></td><td><div><div>Unable to update the welcome message sequence.</div></div></td><td><div><div>Check all fields and the sequence ID for correctness. Check that the access token has the necessary permissions for the WhatsApp business account.</div></div></td></tr><tr><td><div><div>`4027007`</div><div>API unavailable</div></div></td><td><div><div>The API being accessed is not available for use yet.</div></div></td><td><div><div>Wait a day or two for the API to become available and try again.</div></div></td></tr><tr><td><div><div>`4027010`</div><div>Missing parameter</div></div></td><td><div><div>One or more required parameters is missing.</div></div></td><td><div><div>Check all the documentation and ensure the required parameters are present.</div></div></td></tr><tr><td><div><div>`4027012`</div><div>Sequence used in an ad</div></div></td><td><div><div>The welcome message sequence is linked to an active ad and cannot be updated or deleted.</div></div></td><td><div><div>Disconnect the sequence from the ad and try again.</div></div></td></tr><tr><td><div><div>`4027017`</div><div>Could not load the sequence</div></div></td><td><div><div>Could not load the sequence being updated or deleted.</div></div></td><td><div><div>The welcome message sequence either does not exist, or you do not have permission to access it. Please check the access token and make sure you have the required permissions.</div></div></td></tr></tbody></table>

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