I have pass all headers still getting "Authorization has been denied for this request" error always. I'm trying to uploading image

[divyesh008]

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Bug Information

Version Number of Plugin: 1.4.0
Device Tested On: iPhone 6
Simulator Tested On:
Version of VS: 8.0.2 (build 23)
Version of Xamarin:12.8.0.0
Versions of other things you are using:
Operating System
Mac OS X 10.14.3
Darwin 18.2.0 Darwin Kernel Version 18.2.0

Steps to reproduce the Behavior

Use this plugin for upload document and images

Expected Behavior

Upload file and show progress bar and after success show success message

Actual Behavior

getting "Authorization has been denied for this request" error always

Code snippet

Dictionary<string, string> headers = new Dictionary<string, string>();
headers.Add("Authorization", AccountInfo.AccessToken);
headers.Add("Content-Type", "application/x-www-form-urlencoded");

        CrossFileUploader.Current.UploadFileAsync(GlobalConstant.ApiUrl + "/api/files/proposalGroup?proposalId=" + ProposalId, new FileBytesItem("document1", docData, filename), headers);


        CrossFileUploader.Current.FileUploadCompleted +=(sender, e) => 
        {
            //Hide Progress bar
        };
        CrossFileUploader.Current.FileUploadError += (sender, e) => 
        { 
        };
        CrossFileUploader.Current.FileUploadProgress +=(sender, e) => 
        { 
            //show progress bar
        };

Screenshotst