Slack Webhook to List - Data Not Matching Column Types Error

How To
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1

Issue:

I’m trying to integrate a Slack workflow using a webhook trigger in Make.com to add an item to a list. However, when sending data from Postman, I get the error:

:backhand_index_pointing_right: Add an item to a list — The data passed in does not match the column types. Please update the mappings for this step."

What I’ve Tried:

  1. Ensured the webhook receives data correctly.
  2. Verified that the “Name” field in Slack’s list step is mapped correctly.
  3. Checked the expected column types in Slack Workflow Builder.
  4. Sent a properly formatted JSON payload from Postman:

{
“name”: “Test Task”
}

  1. Looked at the Activity Log for errors, but still facing the issue.

Has anyone encountered this before? Any suggestions would be appreciated!