the request was aborted could not create ssl/tls secure channel. c# restsharp

 ServicePointManager.Expect100Continue = true;
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls
                   | SecurityProtocolType.Tls11
                   | SecurityProtocolType.Tls12
                   | SecurityProtocolType.Ssl3;

//Add this line of code before RestClient
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;