diff --git a/source/Cute.Lib/Contentful/BulkActions/Actions/UpsertBulkAction.cs b/source/Cute.Lib/Contentful/BulkActions/Actions/UpsertBulkAction.cs
index ef83b6b..bae2e68 100644
--- a/source/Cute.Lib/Contentful/BulkActions/Actions/UpsertBulkAction.cs
+++ b/source/Cute.Lib/Contentful/BulkActions/Actions/UpsertBulkAction.cs
@@ -428,30 +428,41 @@ private bool ValuesDiffer(
 
         var contentDisplayField = _contentType!.DisplayField;
 
-        foreach (var (fieldName, value) in localFlatEntry)
-        {
-            if (fieldName.StartsWith("sys.")) continue;
+        var allFieldNames = localFlatEntry.Keys
+            .Concat(cloudFlatEntry.Keys)
+            .Where(fieldName => !fieldName.StartsWith("sys."))
+            .ToHashSet();
 
-            string? oldValue = null;
+        foreach (var fieldName in allFieldNames)
+        {
+            var existsInLocal = localFlatEntry.TryGetValue(fieldName, out var localValue);
+            var existsInCloud = cloudFlatEntry.TryGetValue(fieldName, out var cloudValue);
 
-            if (cloudFlatEntry.TryGetValue(fieldName, out var oldValueObj))
+            if (existsInLocal)
             {
-                oldValue = cloudFlatEntry[fieldName]?.ToString();
-            }
+                string? oldValue = cloudValue?.ToString();
 
-            var isFieldChanged = serializer.CompareAndUpdateEntry(cloudFlatEntry, fieldName, value, _appendFields);
+                var isFieldChanged = serializer.CompareAndUpdateEntry(cloudFlatEntry, fieldName, localValue, _appendFields);
 
-            if (isFieldChanged)
+                if (isFieldChanged)
+                {
+                    changedFields.Add(fieldName, (oldValue, localValue));
+                    isChanged = true;
+                }
+            }
+            else if (existsInCloud && !string.IsNullOrEmpty(cloudValue?.ToString()))
             {
-                changedFields.Add(fieldName, (oldValue, value));
+                changedFields.Add(fieldName, (cloudValue?.ToString(), null));
+                cloudFlatEntry.Remove(fieldName);
+                isChanged = true;
             }
-
-            isChanged = isFieldChanged || isChanged;
         }
 
         if (isChanged)
         {
-            var newEntryName = localFlatEntry.ContainsKey($"{contentDisplayField}.{defaultLocale}") ? localFlatEntry[$"{contentDisplayField}.{defaultLocale}"] : localFlatEntry[$"{_matchField}.{defaultLocale}"];
+            var newEntryName = localFlatEntry.ContainsKey($"{contentDisplayField}.{defaultLocale}")
+                ? localFlatEntry[$"{contentDisplayField}.{defaultLocale}"]
+                : localFlatEntry[$"{_matchField}.{defaultLocale}"];
 
             NotifyUserInterface($"'{_contentTypeId}' - '{newEntryName}' will be updated.", progressUpdater);