Play FakeMultipartRequest unexpected end of input

I am breaking my head with testing my controller.

I have the following test code that tests a simple csv upload, The file exists and the endpoint work when I try to upload from some simple rest client like postmen

I am getting: 400 unexpected end of input.

Tried everything i can think of. Thanks

    val controller = application.injector.instanceOf[MyController]
    val file = play.api.libs.Files.TemporaryFile(FileUtils.toFile(getClass.getResource(MyCSV)))
    val data = new MultipartFormData(Map(), List(
      FilePart("file", "sample.csv", Some("application/csv"), file)
    ), List())
    def fakeMultipartRequest: FakeRequest[AnyContentAsMultipartFormData] = FakeRequest(HttpVerbs.POST, "/upload")
      .withHeaders(("Content-Type", "multipart/form-data; boundary=***boundry***"))
      .withMultipartFormDataBody(data)  
    val result = call(controller.upload(), fakeMultipartRequest)
    val str = contentAsString(result)
    status(result) shouldBe OK

and my controller is simple:

def upload() = Action.async(parse.multipartFormData) { implicit request => ...