diff --git a/repository/src/main/java/org/apache/atlas/repository/store/graph/v2/EntityGraphMapper.java b/repository/src/main/java/org/apache/atlas/repository/store/graph/v2/EntityGraphMapper.java
index 208cf1b733..f18d802ffc 100644
--- a/repository/src/main/java/org/apache/atlas/repository/store/graph/v2/EntityGraphMapper.java
+++ b/repository/src/main/java/org/apache/atlas/repository/store/graph/v2/EntityGraphMapper.java
@@ -2253,7 +2253,7 @@ private void addOrRemoveInternalAttr(AtlasVertex toVertex, String internalAttr,
 
         if (CollectionUtils.isNotEmpty(createdElements)) {
             List<String> assetGuids = createdElements.stream().map(x -> ((AtlasEdge) x).getOutVertex().getProperty("__guid", String.class)).collect(Collectors.toList());
-            portGuids.addAll(assetGuids);
+            portGuids = (List<String>) CollectionUtils.union(portGuids, assetGuids);
         }
 
         if (CollectionUtils.isNotEmpty(deletedElements)) {