diff --git a/lib/features/base/widget/default_field/default_autocomplete_input_field_widget.dart b/lib/features/base/widget/default_field/default_autocomplete_input_field_widget.dart
index ce094b352..25b31c10f 100644
--- a/lib/features/base/widget/default_field/default_autocomplete_input_field_widget.dart
+++ b/lib/features/base/widget/default_field/default_autocomplete_input_field_widget.dart
@@ -1,5 +1,5 @@
 import 'dart:async';
-import 'dart:math';
+import 'dart:math' as math;
 
 import 'package:core/presentation/extensions/color_extension.dart';
 import 'package:core/presentation/resources/image_paths.dart';
@@ -11,6 +11,7 @@ import 'package:flutter/services.dart';
 import 'package:get/get.dart';
 import 'package:jmap_dart_client/jmap/mail/email/email_address.dart';
 import 'package:model/extensions/email_address_extension.dart';
+import 'package:model/extensions/list_email_address_extension.dart';
 import 'package:model/mailbox/expand_mode.dart';
 import 'package:super_tag_editor/tag_editor.dart';
 import 'package:tmail_ui_user/features/base/widget/default_field/default_autocomplete_tag_item_widget.dart';
@@ -193,7 +194,9 @@ class _DefaultAutocompleteInputFieldWidgetState
             suggestionValid: suggestionValid,
             highlight: highlight,
             onSelectedAction: (emailAddress) {
-              _setStateSafety(() => _currentListEmailAddress.add(emailAddress));
+              if (!_isDuplicated(emailAddress.emailAddress)) {
+                _setStateSafety(() => _currentListEmailAddress.add(emailAddress));
+              }
               _updateListEmailAddressAction();
               tagEditorState.resetTextField();
               tagEditorState.closeSuggestionBox();
@@ -268,19 +271,12 @@ class _DefaultAutocompleteInputFieldWidgetState
         processedQuery,
         limit: limit,
       );
-      final listSuggestionEmailAddress =
-          listEmailAddress.map((emailAddress) => _toSuggestionEmailAddress(
-                emailAddress,
-                _currentListEmailAddress,
-              ));
+      final listSuggestionEmailAddress = listEmailAddress
+          .map(_toSuggestionEmailAddress);
+
       displayedSuggestion.addAll(listSuggestionEmailAddress);
     }
 
-    displayedSuggestion.addAll(_matchedSuggestionEmailAddress(
-      processedQuery,
-      _currentListEmailAddress,
-    ));
-
     final currentTextOnTextField = widget.controller?.text ?? '';
     if (currentTextOnTextField.isEmpty) {
       return [];
@@ -293,17 +289,11 @@ class _DefaultAutocompleteInputFieldWidgetState
     if (inputEmail.isEmpty) {
       return false;
     }
-    return _currentListEmailAddress
-        .map((emailAddress) => emailAddress.email)
-        .nonNulls
-        .contains(inputEmail);
+    return _currentListEmailAddress.isDuplicatedEmail(inputEmail.trim());
   }
 
-  SuggestionEmailAddress _toSuggestionEmailAddress(
-    EmailAddress item,
-    List<EmailAddress> addedEmailAddresses,
-  ) {
-    if (addedEmailAddresses.contains(item)) {
+  SuggestionEmailAddress _toSuggestionEmailAddress(EmailAddress item) {
+    if (_currentListEmailAddress.isDuplicatedEmail(item.emailAddress)) {
       return SuggestionEmailAddress(
         item,
         state: SuggestionEmailState.duplicated,
@@ -313,18 +303,6 @@ class _DefaultAutocompleteInputFieldWidgetState
     }
   }
 
-  Iterable<SuggestionEmailAddress> _matchedSuggestionEmailAddress(
-    String query,
-    List<EmailAddress> addedEmailAddress,
-  ) {
-    return addedEmailAddress
-        .where((addedMail) => addedMail.emailAddress.contains(query))
-        .map((emailAddress) => SuggestionEmailAddress(
-              emailAddress,
-              state: SuggestionEmailState.duplicated,
-            ));
-  }
-
   void _updateListEmailAddressAction() {
     widget.onUpdateListEmailAddressAction?.call(
       widget.field,
@@ -396,7 +374,7 @@ class _DefaultAutocompleteInputFieldWidgetState
 
   double? _getSuggestionBoxWidth(double maxWidth) {
     if (maxWidth < ResponsiveUtils.minTabletWidth) {
-      final newWidth = min(maxWidth, 300.0);
+      final newWidth = math.min(maxWidth, 300.0);
       return newWidth;
     } else {
       return null;
@@ -405,8 +383,7 @@ class _DefaultAutocompleteInputFieldWidgetState
 
   void _onAcceptWithDetails(DraggableEmailAddress draggableEmailAddress) {
     if (draggableEmailAddress.filterField != widget.field) {
-      if (!_currentListEmailAddress
-          .contains(draggableEmailAddress.emailAddress)) {
+      if (!_isDuplicated(draggableEmailAddress.emailAddress.emailAddress)) {
         _setStateSafety(() {
           _currentListEmailAddress.add(draggableEmailAddress.emailAddress);
           _isDragging = false;
diff --git a/lib/features/composer/presentation/widgets/recipient_composer_widget.dart b/lib/features/composer/presentation/widgets/recipient_composer_widget.dart
index 36fbe86fb..c81c017b8 100644
--- a/lib/features/composer/presentation/widgets/recipient_composer_widget.dart
+++ b/lib/features/composer/presentation/widgets/recipient_composer_widget.dart
@@ -16,6 +16,7 @@ import 'package:get/get.dart';
 import 'package:jmap_dart_client/jmap/mail/email/email_address.dart';
 import 'package:model/email/prefix_email_address.dart';
 import 'package:model/extensions/email_address_extension.dart';
+import 'package:model/extensions/list_email_address_extension.dart';
 import 'package:super_tag_editor/tag_editor.dart';
 import 'package:tmail_ui_user/features/composer/presentation/extensions/list_address_extension.dart';
 import 'package:tmail_ui_user/features/composer/presentation/extensions/list_named_address_extension.dart';
@@ -270,7 +271,9 @@ class _RecipientComposerWidgetState extends State<RecipientComposerWidget> {
                         suggestionValid: suggestionValid,
                         highlight: highlight,
                         onSelectedAction: (emailAddress) {
-                          stateSetter(() => _currentListEmailAddress.add(emailAddress));
+                          if (!_isDuplicatedRecipient(emailAddress.emailAddress)) {
+                            stateSetter(() => _currentListEmailAddress.add(emailAddress));
+                          }
                           _updateListEmailAddressAction();
                           tagEditorState.resetTextField();
                           tagEditorState.closeSuggestionBox();
@@ -434,14 +437,11 @@ class _RecipientComposerWidgetState extends State<RecipientComposerWidget> {
         limit: limit,
       );
       final listSuggestionEmailAddress = listEmailAddress
-        .map((emailAddress) => _toSuggestionEmailAddress(
-          emailAddress,
-          _currentListEmailAddress));
+        .map(_toSuggestionEmailAddress);
+
       tmailSuggestion.addAll(listSuggestionEmailAddress);
     }
 
-    tmailSuggestion.addAll(_matchedSuggestionEmailAddress(processedQuery, _currentListEmailAddress));
-
     final currentTextOnTextField = widget.controller?.text ?? '';
     if (currentTextOnTextField.isEmpty) {
       return [];
@@ -453,27 +453,17 @@ class _RecipientComposerWidgetState extends State<RecipientComposerWidget> {
   bool _isDuplicatedRecipient(String inputEmail) {
     if (inputEmail.trim().isEmpty) return false;
 
-    return _currentListEmailAddress
-      .any((emailAddress) => emailAddress.email?.trim() == inputEmail.trim());
+    return _currentListEmailAddress.isDuplicatedEmail(inputEmail.trim());
   }
 
-  SuggestionEmailAddress _toSuggestionEmailAddress(EmailAddress item, List<EmailAddress> addedEmailAddresses) {
-    if (addedEmailAddresses.contains(item)) {
+  SuggestionEmailAddress _toSuggestionEmailAddress(EmailAddress item) {
+    if (_currentListEmailAddress.isDuplicatedEmail(item.emailAddress)) {
       return SuggestionEmailAddress(item, state: SuggestionEmailState.duplicated);
     } else {
       return SuggestionEmailAddress(item);
     }
   }
 
-  Iterable<SuggestionEmailAddress> _matchedSuggestionEmailAddress(String query, List<EmailAddress> addedEmailAddress) {
-    return addedEmailAddress
-      .where((addedMail) => addedMail.emailAddress.contains(query))
-      .map((emailAddress) => SuggestionEmailAddress(
-        emailAddress,
-        state: SuggestionEmailState.duplicated
-      ));
-  }
-
   void _handleGapBetweenTagChangedAndFindSuggestion() {
     log('_RecipientComposerWidgetState::_handleGapBetweenTagChangedAndFindSuggestion:Timeout');
   }
@@ -571,7 +561,7 @@ class _RecipientComposerWidgetState extends State<RecipientComposerWidget> {
     log('_RecipientComposerWidgetState::_handleAcceptDraggableEmailAddressAction: $draggableEmailAddress');
     if (draggableEmailAddress.composerId == widget.composerId) {
       if (draggableEmailAddress.filterField != widget.prefix.filterField) {
-        if (!_currentListEmailAddress.contains(draggableEmailAddress.emailAddress)) {
+        if (!_isDuplicatedRecipient(draggableEmailAddress.emailAddress.emailAddress)) {
           stateSetter(() {
             _currentListEmailAddress.add(draggableEmailAddress.emailAddress);
             _isDragging = false;
@@ -589,7 +579,7 @@ class _RecipientComposerWidgetState extends State<RecipientComposerWidget> {
         }
       }
     } else {
-      if (!_currentListEmailAddress.contains(draggableEmailAddress.emailAddress)) {
+      if (!_isDuplicatedRecipient(draggableEmailAddress.emailAddress.emailAddress)) {
         stateSetter(() {
           _currentListEmailAddress.add(draggableEmailAddress.emailAddress);
           _isDragging = false;