“Unable to connect to the remote server” when I call a rest Api

问题

I am getting Unable to connect to the remote server response when I call a rest API

var client = new RestClient { BaseUrl = new Uri(ConfigurationManager.AppSettings["WalletUrl"]) };
var hgh = ConfigurationManager.AppSettings["GetWalletRequest"];
var requests = new RestRequest(Method.POST)
{
    RequestFormat = DataFormat.Json
};
requests.AddHeader("content-type", "application/json");
requests.AddParameter("application/json", req, ParameterType.RequestBody);
requests.AddBody(req);
var response = client.Execute(requests);

来源：https://stackoverflow.com/questions/56740577/unable-to-connect-to-the-remote-server-when-i-call-a-rest-api