diff --git a/src/neo/SmartContract/InteropService.Storage.cs b/src/neo/SmartContract/InteropService.Storage.cs
index 98aee6d9f9..609ebca028 100644
--- a/src/neo/SmartContract/InteropService.Storage.cs
+++ b/src/neo/SmartContract/InteropService.Storage.cs
@@ -40,7 +40,7 @@ private static long GetStoragePrice(EvaluationStack stack, StoreView snapshot)
                     Key = key.GetSpan().ToArray()
                 };
                 var skeyValue = snapshot.Storages.TryGet(skey);
-                if (skeyValue is null)
+                if (skeyValue is null || skeyValue.Value is null)
                     newDataSize += key.GetByteLength();
                 else if (newDataSize <= skeyValue.Value.Length)
                     newDataSize = 1;