Urgent: Meta Webhook Verification Failing for n8n.cloud Instance

Questions
1

Hello n8n Support Team,

I am unable to verify a Meta (Facebook/Instagram) webhook on my n8n.cloud instance. I have spent a lot of time troubleshooting this and have confirmed the problem is not in my workflow configuration.

The Problem: When I try to verify my webhook from the Meta Developer Hub, it fails with the error: “The callback URL or verify token couldn’t be validated.”

However, my n8n workflow successfully receives the verification request every single time. The execution log shows the GET request from Meta with the correct hub.mode, hub.challenge, and hub.verify_token.

My n8n Instance URL: https://getconnectai.app.n8n.cloud/

Troubleshooting Steps Taken:

  • Confirmed the “Respond Immediately” setting is active.

  • Confirmed the HTTP Method is “All Methods”.

  • Even built a manual 3-node workflow to craft the response perfectly.

  • The result is always the same: n8n shows a successful execution, but Meta shows an error.

The last failed attempt occurred on [ October 12, 2025, around 10:25 AM CEST].

I have attached two screenshots as proof:

  1. The successful execution in my n8n workflow.

    image
    image1857×844 108 KB

  2. The error message in the Meta Developer Hub.

    image

This proves the issue is happening after my n8n instance receives the request. Can you please investigate your server logs to see why the response is not being accepted by Meta?

Thank you for your help.

2

Hi @biskota, this thread suggests that

You must return an http response of the hub.challenge token as a plain text.

Try adding the option “Response Data” and return the hub.challenge (or hub_challenge depending on what params you get in the webhook request). Another thread I have found also suggests that you need

Response Code: 200

Response Header Name: Content-Type
Response Header Value: text