diff --git a/lib/pages/space_management_v2/modules/space_details/domain/models/space_details_model.dart b/lib/pages/space_management_v2/modules/space_details/domain/models/space_details_model.dart
index b3e436b1..ec3c9f81 100644
--- a/lib/pages/space_management_v2/modules/space_details/domain/models/space_details_model.dart
+++ b/lib/pages/space_management_v2/modules/space_details/domain/models/space_details_model.dart
@@ -40,16 +40,6 @@ class SpaceDetailsModel extends Equatable {
     );
   }
 
-  Map<String, dynamic> toJson() {
-    return {
-      'uuid': uuid,
-      'spaceName': spaceName,
-      'icon': icon,
-      'productAllocations': productAllocations.map((e) => e.toJson()).toList(),
-      'subspaces': subspaces.map((e) => e.toJson()).toList(),
-    };
-  }
-
   SpaceDetailsModel copyWith({
     String? uuid,
     String? spaceName,
@@ -89,14 +79,6 @@ class ProductAllocation extends Equatable {
     );
   }
 
-  Map<String, dynamic> toJson() {
-    return {
-      'uuid': uuid,
-      'product': product.toJson(),
-      'tag': tag.toJson(),
-    };
-  }
-
   ProductAllocation copyWith({
     String? uuid,
     Product? product,
@@ -134,14 +116,6 @@ class Subspace extends Equatable {
     );
   }
 
-  Map<String, dynamic> toJson() {
-    return {
-      'uuid': uuid,
-      'name': name,
-      'productAllocations': productAllocations.map((e) => e.toJson()).toList(),
-    };
-  }
-
   Subspace copyWith({
     String? uuid,
     String? name,
diff --git a/lib/pages/space_management_v2/modules/space_details/presentation/widgets/space_sub_spaces_dialog.dart b/lib/pages/space_management_v2/modules/space_details/presentation/widgets/space_sub_spaces_dialog.dart
index 9e81c323..8faac548 100644
--- a/lib/pages/space_management_v2/modules/space_details/presentation/widgets/space_sub_spaces_dialog.dart
+++ b/lib/pages/space_management_v2/modules/space_details/presentation/widgets/space_sub_spaces_dialog.dart
@@ -37,7 +37,7 @@ class _SpaceSubSpacesDialogState extends State<SpaceSubSpacesDialog> {
         ..._subspaces,
         Subspace(
           name: name,
-          uuid: const Uuid().v4(),
+          uuid: '${const Uuid().v4()}-NewTag',
           productAllocations: const [],
         ),
       ];
diff --git a/lib/pages/space_management_v2/modules/tags/domain/models/tag.dart b/lib/pages/space_management_v2/modules/tags/domain/models/tag.dart
index 370bdf47..c5bccdbb 100644
--- a/lib/pages/space_management_v2/modules/tags/domain/models/tag.dart
+++ b/lib/pages/space_management_v2/modules/tags/domain/models/tag.dart
@@ -3,41 +3,19 @@ import 'package:equatable/equatable.dart';
 class Tag extends Equatable {
   final String uuid;
   final String name;
-  final String createdAt;
-  final String updatedAt;
 
   const Tag({
     required this.uuid,
     required this.name,
-    required this.createdAt,
-    required this.updatedAt,
   });
 
-  factory Tag.empty() => const Tag(
-        uuid: '',
-        name: '',
-        createdAt: '',
-        updatedAt: '',
-      );
-
   factory Tag.fromJson(Map<String, dynamic> json) {
     return Tag(
       uuid: json['uuid'] as String,
       name: json['name'] as String,
-      createdAt: json['createdAt'] as String,
-      updatedAt: json['updatedAt'] as String,
     );
   }
 
-  Map<String, dynamic> toJson() {
-    return {
-      'uuid': uuid,
-      'name': name,
-      'createdAt': createdAt,
-      'updatedAt': updatedAt,
-    };
-  }
-
   @override
-  List<Object?> get props => [uuid, name, createdAt, updatedAt];
+  List<Object?> get props => [uuid, name];
 }
diff --git a/lib/pages/space_management_v2/modules/tags/presentation/widgets/assign_tags_dialog.dart b/lib/pages/space_management_v2/modules/tags/presentation/widgets/assign_tags_dialog.dart
index 3cab4abe..3f6d42ab 100644
--- a/lib/pages/space_management_v2/modules/tags/presentation/widgets/assign_tags_dialog.dart
+++ b/lib/pages/space_management_v2/modules/tags/presentation/widgets/assign_tags_dialog.dart
@@ -214,9 +214,12 @@ class _AssignTagsDialogState extends State<AssignTagsDialog> {
               for (final product in newProducts) {
                 _space.productAllocations.add(
                   ProductAllocation(
-                    uuid: const Uuid().v4(),
+                    uuid: '${const Uuid().v4()}-NewProductUuid',
                     product: product,
-                    tag: Tag.empty(),
+                    tag: Tag(
+                      uuid: '${const Uuid().v4()}-NewTag',
+                      name: '',
+                    ),
                   ),
                 );
               }
diff --git a/lib/pages/space_management_v2/modules/tags/presentation/widgets/product_tag_field.dart b/lib/pages/space_management_v2/modules/tags/presentation/widgets/product_tag_field.dart
index 8bbf379d..30282123 100644
--- a/lib/pages/space_management_v2/modules/tags/presentation/widgets/product_tag_field.dart
+++ b/lib/pages/space_management_v2/modules/tags/presentation/widgets/product_tag_field.dart
@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:syncrow_web/pages/space_management_v2/modules/tags/domain/models/tag.dart';
 import 'package:syncrow_web/utils/color_manager.dart';
 import 'package:syncrow_web/utils/extension/build_context_x.dart';
+import 'package:uuid/uuid.dart';
 
 class ProductTagField extends StatefulWidget {
   final List<Tag> items;
@@ -53,13 +54,8 @@ class _ProductTagFieldState extends State<ProductTagField> {
   void _submit(String value) {
     final lowerCaseValue = value.toLowerCase();
     final selectedTag = widget.items.firstWhere(
-      (tag) => tag.name.toLowerCase() == lowerCaseValue,
-      orElse: () => Tag(
-        name: value,
-        uuid: '',
-        createdAt: '',
-        updatedAt: '',
-      ),
+      (e) => e.name.toLowerCase() == lowerCaseValue,
+      orElse: () => Tag(uuid: '${const Uuid().v4()}-NewTag', name: value),
     );
     widget.onSelected(selectedTag);
     _closeDropdown();
diff --git a/lib/pages/space_management_v2/modules/update_space/data/services/remote_update_space_service.dart b/lib/pages/space_management_v2/modules/update_space/data/services/remote_update_space_service.dart
index b595e2b9..a70d3b85 100644
--- a/lib/pages/space_management_v2/modules/update_space/data/services/remote_update_space_service.dart
+++ b/lib/pages/space_management_v2/modules/update_space/data/services/remote_update_space_service.dart
@@ -19,7 +19,7 @@ class RemoteUpdateSpaceService implements UpdateSpaceService {
       final path = await _makeUrl(param);
       await _httpService.put(
         path: path,
-        body: param.space.toJson(),
+        body: param.toJson(),
         expectedResponseModel: (data) {
           final response = data as Map<String, dynamic>;
           final isSuccess = response['success'] as bool;
diff --git a/lib/pages/space_management_v2/modules/update_space/domain/params/update_space_param.dart b/lib/pages/space_management_v2/modules/update_space/domain/params/update_space_param.dart
index 884cd581..97fefe03 100644
--- a/lib/pages/space_management_v2/modules/update_space/domain/params/update_space_param.dart
+++ b/lib/pages/space_management_v2/modules/update_space/domain/params/update_space_param.dart
@@ -13,33 +13,29 @@ class UpdateSpaceParam {
     return {
       'spaceName': space.spaceName,
       'icon': space.icon,
-      'subspaces': space.subspaces
-          .map(
-            (e) => {
-              'subspaceName': e.name,
-              'productAllocations': e.productAllocations
-                  .map(
-                    (e) => {
-                      'name': e.tag.name,
-                      'productUuid': e.product.uuid,
-                      'uuid': e.uuid,
-                    },
-                  )
-                  .toList(),
-              'uuid': e.uuid,
-            },
-          )
-          .toList(),
-      'productAllocations': space.productAllocations
-          .map(
-            (e) => {
-              'tagName': e.tag.name,
-              'tagUuid': e.tag.uuid,
-              'productUuid': e.product.uuid,
-            },
-          )
-          .toList(),
-      'spaceModelUuid': space.uuid,
+      'subspaces': space.subspaces.map((e) => e._toJson()).toList(),
+      'productAllocations':
+          space.productAllocations.map((e) => e._toJson()).toList(),
+    };
+  }
+}
+
+extension _ProductAllocationToJson on ProductAllocation {
+  Map<String, dynamic> _toJson() {
+    final isNewTag = tag.uuid.isEmpty;
+    return <String, dynamic>{
+      if (isNewTag) 'tagName': tag.name else 'tagUuid': tag.uuid,
+      'productUuid': product.uuid,
+    };
+  }
+}
+
+extension _SubspaceToJson on Subspace {
+  Map<String, dynamic> _toJson() {
+    final isNewSubspace = uuid.endsWith('-NewTag');
+    return <String, dynamic>{
+      if (isNewSubspace) 'subspaceName': name else 'uuid': uuid,
+      'productAllocations': productAllocations.map((e) => e._toJson()).toList(),
     };
   }
 }