Creator API v2 Add Records - Not adding SubForm data

Creator API v2 Add Records - Not adding SubForm data

I have a formula in creator where I am trying to enter a new record into another creator form. All of the fields in the main part of the form pull in without issue but I cannot insert any subform data into a new record, or udpate an existing record using the creator v2 API even though I have everything formatted properly. Has anyone else had this issue? What is it that I am doing wrong?

I have created a test form with just a single line field (called Main_Field), and a subform (called SubForm) with a single line field (called Subform_Field). 

This is my code (with the url taken out): 
  1. dataMap = Map();
  2. formMap = Map();
  3. subformMap = Map();
  4. subformList = List();

  6. subformMap.put("Subform_Field", "Testing");
  7. subformList.add(subformMap);

  9. formMap.put("Main_Field", "Testing");
  10. formMap.put("SubForm", subformList);
  11. dataMap.put("data", formMap);
  12. info dataMap;

  14. testing = invokeurl
  15. [
    1. url: "https://creator.zoho.com/api/v2/..."
    2. type: POST
    3. parameters: dataMap.toString()
    4. connection: "zoho_creator"
  16. ];
  17. info testing;

and the output:

{"data":{"Main_Field":"Testing","SubForm":[{"Subform_Field":"Testing"}]}}
{"code":3000,"data":{"ID":"4107384000000323365"},"message":"Data Added Successfully"}

However in the record I only see the "Testing" created in the Main_Field, there is absolutely nothing in the Subform_Field. 

What am I doing wrong?