diff --git a/lib/utility.dart b/lib/utility.dart
index bd775bc..0052816 100644
--- a/lib/utility.dart
+++ b/lib/utility.dart
@@ -66,13 +66,13 @@ class Utility {
         newIndex++;
 
         if (oldIndex < oldWords.length && newIndex < newWords.length) {
-          var nextOldWord = oldWords[oldIndex];
           var newSubIndex = newIndex;
           var oldSubIndex = oldIndex;
           while (newSubIndex < newWords.length &&
-              newWords[newSubIndex].text != nextOldWord.text) {
+              newWords[newSubIndex].text != oldWords[oldSubIndex].text) {
+            //nextOldWord was not incremented in the loop hence used indexing for nextOldWord
             WordDelta wordDelta =
-                WordDelta(old: nextOldWord, modified: newWords[newSubIndex]);
+                WordDelta(old: oldWords[oldSubIndex], modified: newWords[newSubIndex]);
             delta.wordDeltas.add(wordDelta);
             newSubIndex++;
             oldSubIndex++;