var options = new RestClientOptions("https://apitest.nilvera.com")
{
MaxTimeout = -1,
};
var client = new RestClient(options);
var request = new RestRequest("/edespatch/Send/Base64String/Preview", Method.Post);
request.AddHeader("Content-Type", "application/json");
request.AddHeader("Authorization", "APIKEY");
var body = new
{
ZIPFileBase64 = "string",
Alias = "string",
TemplateUUID = "3fa85f64-5717-4562-b3fc-2c963f66afa6"
};
request.AddJsonBody(body);
RestResponse response = await client.ExecuteAsync(request);
Console.WriteLine(response.Content);