Calling a Zoho Flow from a Deluge script

Calling a Zoho Flow from a Deluge script

I wish to call a Zoho Flow from a deluge script (that is attached to a button in Zoho CRM).

The deluge code I have been experimenting with is as follows:


(the URL address and zapikey have been replaced with random text - the actual URL comes from Zoho Flow) 

InquiryID is the id of an inquiry.

In Zoho Flow, I set up a webhook event of type form, plain text.

During Zoho Flow tests of the webhook, I can see the webhook being called, but no data payload is showing up - that is, the InquiryID data is not being picked up from the call.

What I am doing wrong?

Best regards,
Joe