So i tried this using the Bubble API instead to test this on a common app, I managed to make it work on Postman directly using your method, but I get a 404 error when using the API connector.

The example is just a test Datatype which has a field text-value.

Do you see an error in what I made ? Or do you have an idea as to what could be going wrong in the behind the scenes ?

Content-Type : multipart/form-data; boundary=xxxxxx