diff --git a/AirPlaneWithRadar/AirPlaneWithRadar/SetPlaneGeneric.cs b/AirPlaneWithRadar/AirPlaneWithRadar/SetPlaneGeneric.cs
index 45b9dc2..291aa24 100644
--- a/AirPlaneWithRadar/AirPlaneWithRadar/SetPlaneGeneric.cs
+++ b/AirPlaneWithRadar/AirPlaneWithRadar/SetPlaneGeneric.cs
@@ -20,17 +20,13 @@ namespace AirPlaneWithRadar
         }
         public int Insert(T plain)
         {
-            if (_places.Count == _maxCount)
-            {
-                return -1;
-            }
-            _places.Insert(0, plain);
-
+            
+            Insert(plain, 0);
             return _places.Count;
         }
         public int Insert(T plain, int position)
         {
-            if (position < 0 || _places.Count < position||position > _maxCount)
+            if (position < 0 || _places.Count < position||position > _maxCount || _places.Count == _maxCount)
                 return -1;
             else if (plain == null)
                 return -1;