سلام خدمت تمامی دوستان عزیز

(((( ویرایش شد | مشکل حل شد ))))

کدهای زیر کار میکنن :

var client = new RestClient("https://api.payping.ir/v1/pay");
var request = new RestRequest(Method.POST);
request.AddHeader("authorization", "Bearer xxxxxxxxxxxxxxxxxxxxx");
request.AddHeader("content-type", "application/json");
request.AddHeader("accept", "application/json");
var model = new
{
    Amount = 100,
    PayerIdentity = "string",
    PayerName = "string",
    Description = "string",
    ReturnUrl = "string",
    ClientRefId = "string"
};
request.AddJsonBody(model);
IRestResponse response = client.Execute(request);