last ...

Providers/XBaseTagProvider.cs

@@ -295,19 +295,19 @@ namespace xTagService.Providers
 
             //
             // Validate ...
-            var isValid = !model.IsNullOrDefault() &&
+            result = !model.IsNullOrDefault() &&
                 !model.Tag.IsNullOrEmpty() &&
                 model.Id.IsValidIntId() &&
                 !providedForId.IsNull();
-            if (!isValid)
+            if (!result)
             {
                 XException.InvalidArgs.Throw();
             }
 
             //
             // Check Model Exists ...
-            isValid = await TagProvider.IsExists(model.Id);
-            if (!isValid)
+            result = await TagProvider.IsExists(model.Id);
+            if (!result)
             {
                 XException.NotFound.Throw();
             }
@@ -333,9 +333,6 @@ namespace xTagService.Providers
             //
             // Here means there is not any reference to ProvidedForId ...
             int forIndex = await CountReferences(providedForId);
-
-            //
-            // Add Reference to Model ...
             model.References.Add(new XReference<string>
             {
                 Index = forIndex,
@@ -448,7 +445,7 @@ namespace xTagService.Providers
             var reference = model.References
                 .FirstOrDefault(r => r.ProvidedFor == Provider &&
                 r.ReferencedTo == $"{providedForId}");
-            result = !model.IsNullOrDefault();
+            result = !reference.IsNullOrDefault();
             if (!result)
             {
                 XException.ActionFailed.Throw();