Form Field Generator through Rest API V6

I'm attempting to test the functionality of the Adobe Sign Rest API V6, in the model it lists the FormFieldGenerator, and upon further research is a feature that was added in 2020. I have attempted several times to create a test document and using the FormFieldGenerator but the information appears to just be ignored. I found a forum post from April 21, 2023 of someone with the same issue, and he found out that the Anchor Text setting is disabled by default. Is there anyway this can be enabled so I can test this functionality, it is the remaining thing needing to be tested to convince the owner to switch from DocuSign. Currently using a free developer account for the testing purposes, so I'm unable to create a case.

Below is the forum post for reference:

https://community.adobe.com/t5/adobe-acrobat-sign-discussions/adding-form-field-signature-to-a-pdf-using-rest-api-v6/m-p/13742580