Create webrequest failed could not create ssl/tls secure channel code example

Example 1: could not create ssl/tls secure channel

// using System.Net;
ServicePointManager.Expect100Continue = true;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
// Use SecurityProtocolType.Ssl3 if needed for compatibility reasons

Example 2: the request was aborted could not create ssl/tls secure channel. c# restsharp

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