Cannot access a disposed object. Object name: 'System.Net.Http.MultipartFormDataContent'

I am getting the following error:

System.ObjectDisposedException: Cannot access a disposed object. Object name: 'System.Net.Http.MultipartFormDataContent'. 

My code is this:

var content = new MultipartFormDataContent(); 

Then I add a few keys to the content.

After that I have a loop with this code inside:

using (var client = new HttpClient(handler, false)) { var response = client.PostAsync(uri, content).Result; if (response.IsSuccessStatusCode) { var responseContent = response.Content; bytes = responseContent.ReadAsByteArrayAsync().Result; } else { Response.End(); } } 

When it runs second time it gives me the above error.

Any idea why?

Thanks

Update. As suggested changing my code to this: I put this above the loop:

var client = new HttpClient(handler, false); using (client) { var response = client.PostAsync(uri, content).Result; if (response.IsSuccessStatusCode) { var responseContent = response.Content; bytes = responseContent.ReadAsByteArrayAsync().Result; } else { Response.End(); } } 

Now I am getting:

Cannot access a disposed object. Object name: 'System.Net.Http.HttpClient'