Xamarin bug fix needed urgently

We have a Xamarin app that has up until now been working without issue. We are making a simple http post request which returns a 404 error on any url we try. We need someone to debug this locally via teamviewer on our pc. Here is the code public async Task<String> LogInUserAsync(String username, String password) { String encodedUsername = [login to view URL](username); var request = new HttpRequestMessage() { RequestUri = new Uri("[login to view URL]"), Method = [login to view URL], }; String content = [login to view URL]("username={0}&password={1}", encodedUsername, password); [login to view URL] = new StringContent(content, [login to view URL],"application/x-www-form-urlencoded"); HttpResponseMessage response = [login to view URL](request).Result; [login to view URL](request); [login to view URL](response); if ([login to view URL]) { [login to view URL](username, password); [login to view URL](); return "Success"; } else { return [login to view URL](); } } The 'response' returns 404 Not found.