public void HTTPPostRequest_UriFormatException_Test()
        {
            var endpointurl = "any wrong url";
            var action      = "checkouts";
            var request     = new GatewayCheckoutRequest();
            var ex          = Assert.Throws <UriFormatException>(() => _webAPIClient.HTTPPostRequest(endpointurl, action, request, ""));

            Assert.IsTrue(ex.Message.Contains("Invalid URI: The format of the URI could not be determined"));
        }