Need Support | Firefly image fill APIs

I am trying to edit the image by utilizing the masking and the original source image. While using the Firefly image fill APIs, I encountered a problem indicating that Firefly is unable to read or process the images.

I have already experimented with various images, including those created by Firefly itself, but the issue persists.

Has anyone else faced a similar challenge?

Please advise me on what I might be overlooking !

Attached is a screenshot of the Postman collection and the error encountered.

Thanks in Advance !