FormData with file object does not include the file when received by the back end

I am working on an small interface for file uploads in angular and attempting to send the file as form data. Looks like the file is non existent on the back end for some reason though.

When the file is selected I set it as the current file like this:

onFileChange(event){
    this.currentFile = event.target.files[0];
}

In addition to that there is a name and type input the user fills out and then once the form is filled they can submit the form. Here is the code for my submit event:

onSubmit(){
    this.service.fileUpload(this.currentFileName, this.selectedFileType, this.currentFile).subscribe((rslt: any) => {
    alert('submitted!');
  })
}

And the onSubmit function calls the services fileUpload function passing in the name, type and file.

In the service function I am creating formdata and appending the 3 params like this:

packShipFileUpload(fileName: string, fileType: string, file: File){

  let formData: FormData = new FormData();
  formData.append('file', file);
  formData.append('fileName', fileName);
  formData.append('type', fileType);

  let f = formData.get('file'); // This is just me making sure that file is added to the formData

  debugger; //debugging to check formData values

  return this._http.post('/DataGetter/UploadFile', formData, {
    headers: { "Content-Type": "multipart/form-data" }
  });
}

On the back I have an endpoint written in vb.net that so far just looks like this:

    Public Function UploadFile() As String

        Dim fileName = HttpContext.Request.Form.Item("fileName")
        Dim fileType = HttpContext.Request.Form.Item("fileType")
        Dim file = HttpContext.Request.Form.Item("file")

        Console.WriteLine(fileName) //break point here and I inspect the form items.

        Return ""

    End Function

I have ran through with debuggers attached to both the browser and back end application and even made attempts in my js to get the file object from the form data using formData.get('file') and I have verified that the file is added to the formData on the front end. For some reason though the back end always is completely missing that item from the formData.

I have seen several other questions on SO that seem to have similar issue but I have not yet found one that has helped to get this fixed.

Thanks in advance for the help.