Human in the loop feature not receiving response after approval

Below is a list of things to check when your human in the loop workflow isn’t resuming after clicking approve:

1. Verify Your Wait Node (or Webhook) Configuration

The human in the loop pattern in n8n typically relies on a Wait node that resumes execution when an external event (like clicking an approve button) occurs. Double-check that your wait configuration is set to listen for a webhook or the appropriate signal. For example, if you’re using a Wait node with a webhook trigger, make sure the URL is correct and accessible.

2. Ensure the Webhook is Triggered

Even if you see the approve button being clicked in your UI, the associated webhook might not be receiving the callback. To troubleshoot this:

• Check your system logs for any incoming HTTP requests or potential errors in your webhook endpoint.
• Confirm that your deployment (in your case via Railway) exposes the public URL required for accepting incoming webhook calls. A misconfiguration here could prevent the workflow from resuming.

3. Review Your Network and Environment Settings

Since your setup uses PostgreSQL and a certain execution process configuration, make sure that no environment-specific settings or network-related restrictions (such as firewall rules, reverse proxies, or DNS issues) are interfering with the webhook reception.

4. Test Components Individually

• Test the Webhook URL: Try making a manual request (for example, using curl or Postman) to simulate the approval event and see if the wait node picks it up.

  BASHCopied
  curl -X POST https://<your-n8n-domain>/<your-webhook-endpoint> \
    -H "Content-Type: application/json" \
    -d '{"approved": true}'

• Test the Re-start of a Workflow: Run a minimal example workflow with the waiting functionality to ensure that the problem isn’t due to a misconfigured or more complex workflow.

5. Check Workflow and Execution Settings

Since no error is displayed and the workflow simply “keeps waiting,” it could also be that the workflow hasn’t reached its output stage. Ensure that:

• The node following the human approval step is properly connected.
• There isn’t any conditional logic (e.g., IF node) that might be inadvertently blocking the subsequent steps.

By verifying the above areas, you can narrow down whether the issue is caused by the waiting mechanism itself or by network/deployment-related issues. For more details on how the wait functionality works and best practices, consult the n8n documentation on Waiting functionality.

If after these checks your workflow still doesn’t resume, reviewing your logs for webhook errors or misconfigurations should offer further insight.