Hi @mitchnewbie !
I don't know the Make.com platform, but apparently the envelope creation API call is being sent without the fields, or something in the call is incorrect (like the Envelope Custom Fields).
One suggestion would be to enable this user's logs and try to send a new envelope. This way, it will be possible to check how the API call is being generated and verify if the information is being passing to Docusign by Make.com or not. To enable, access the user used for integration > My Preferences > General (menu on the left) > API Request Log > Enable. Create a new envelope and then download the logs.
Another option is to create a case with our Docusign Developer Support team, and they'll be able to assist you better.