I had a look at your Untagging Clients Zap, and it seems that the issue is being caused by how the headers are formatted in your Webhooks by Zapier GET request. Specifically, the headers are currently entered as a single block of JSON, which causes Zapier to send an empty header name, resulting in this error:
 

TypeError: is not a legal HTTP header name

 
Zapier expects headers to be added as individual key-value pairs, not as a full JSON object. Here’s how to fix it:
 
Instead of pasting this entire block into the header field:

{
  "Content-Type": "application/json",
  "uEncoded": "XXXXXXXXXX=",
  "pEncoded": "YYYYYYYYY",
  "orgEncoded": "ZZZZZZZZZ==",
  "Authorization": "Bearer your_secret_key"
}

You’ll want to click “+ Add value set” and enter each header like this:

Make sure you don’t include quotes or brackets — just enter each value exactly as shown above.
 
Once you’ve updated that, the Webhook request should go through successfully and return your accepted quotes from AroFlo.