Which is the correct Content-Type to send an image in a POST request?

I have to send an image in a POST request, along with other information, but I keep getting the “unsupported _media_type” error. Could anyone tell me what I’m doing wrong?.

Here I attach the image
postman1

Here is where I introduce the needed data
postman4

Here is where I set the Content-Type
postman3

And this is the response

    "success": false,
    "code": "unsupported_media_type",
    "message": " The Content-Type of the request is unsupported",
    "status": 400
}