diff --git a/AIParkingApplication/Statistic.cs b/AIParkingApplication/Statistic.cs
index c63b46d..67642f3 100644
--- a/AIParkingApplication/Statistic.cs
+++ b/AIParkingApplication/Statistic.cs
@@ -44,6 +44,10 @@ namespace AIParkingApplication
                 HttpResponseMessage response = await client.GetAsync("/api/statistics");
                 response.EnsureSuccessStatusCode();
                 var vehicle = await response.Content.ReadAsAsync<Vehicle>();
+                if(vehicle == null)
+                {
+                    return;
+                }
                 lblSoLuongXeMay.Invoke(new Action(() =>
                 {
                     lblSoLuongXeMay.Text = vehicle.NumberOfMoto.ToString();