Windows Phone send Bitmap using multipart/form-data - windows-phone-8

Question

My request need to look like this:
Content-Type: multipart/form-data; boundary=---BOUNDARY
-----BOUNDARY
name="receipt_photo"; filename="image_filename.jpg"
Content-Type: image/jpeg
-----BOUNDARY
I am trying to send it using following code
public async static Task addPhotosToReceipt(BitmapImage image, int idReceipt)
{
User user = PhoneApplicationService.Current.State["user"] as User;
if (user.customer.token != null)
{
RestConnector rc = new RestConnector();
byte[] data;
try
{
using (MemoryStream ms = new MemoryStream())
{
WriteableBitmap btmMap = new WriteableBitmap(image);
System.Windows.Media.Imaging.Extensions.SaveJpeg(btmMap, ms, image.PixelWidth, image.PixelHeight, 0, 100);
data = ms.ToArray();
}
string response = await rc.postAsyncData("/api/v1/receipts/" + idReceipt + "/receipt_photos/?token=" + user.customer.token, data);
if (response.Contains("error"))
{
MessageBox.Show(response);
}
}
catch (Exception ex)
{
}
}
}
//in RestConnector class
public async Task<string> postAsyncData(string adress, byte[] file)
{
using (var client = new HttpClient())
{
using (var content = new MultipartFormDataContent("---BOUNDARY"))
{
content.Add(new StringContent("-----BOUNDARY\nname=\"receipt_photo\"; filename=\"image_filename.jpg\"\nContent-Type: image/jpeg\n-----BOUNDARY"));
content.Add(new StreamContent(new MemoryStream(file)));
using (var message = await client.PostAsync(basicUrl + adress, content))
{
var input = await message.Content.ReadAsStringAsync();
return input;
}
}
}
}
In response I should get URL's to uploaded photos, but instead I got URL's to default photos. I think there is something with my request because on android it works fine.
Maybe I choosed wrong way to create byte from my bitmap?