fix invalid signature error in C# console application communicating with Bitstamp API -- 3

I have been working as freelancer since last ~ 5 years,prior to this was working with a MNC as an Sr. Software Professional. Relevant Skills and Experience Expert on C# using .NET framework using Visual Studio 2012 and 2013 -- Expert in VB.NET using VS2012/VS2013 -- WPF and Windows Forms Application -- Expert in ASP.NET,MVC Proposed Milestones $55 USD - API

I am good in Desktop, Mobile and Website building and 5 years development experience. And I am experienced in Desktop and Web development with Microsoft technologies using C#, WPF , UWP, MFC, C++, Java, Python, Android Camera, face detection, alpr, OCR. I have a working experience in web user controls, master pages, css files using technologies like AJAX Toolkit, JQuery, JavaScript, XML, HTML, JSON, Bootstrap, Angular js, php and Wordpress, Shopify, Woocmmerce Website building. I have also good skills in Web scrap using VBA and (c#, vb). .Net, ASP.Net (MVC) also. Excel processing is my talent. When working on a new project, i like to speak with my clients so that i can have a clear understanding of their needs and vision of the project. Thank you in advance for your time and consideration. I look forward working with you soon.