diff --git a/app/Filament/Resources/RequestCharacteristicResource.php b/app/Filament/Resources/RequestCharacteristicResource.php
index 305ef1e..f76f84b 100644
--- a/app/Filament/Resources/RequestCharacteristicResource.php
+++ b/app/Filament/Resources/RequestCharacteristicResource.php
@@ -95,6 +95,7 @@ class RequestCharacteristicResource extends Resource
                                 $set('machine_id', null);
                                 $set('item_id', null);
                                 $set('aufnr', null);
+                                $set('gernr', null);
                                 $set('machine_name', null);
                                 $set('characteristic_approver_master_id', null);
                                 $set('approver_type', null);
@@ -126,6 +127,7 @@ class RequestCharacteristicResource extends Resource
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
                                 $set('item_id', null);
                                 $set('aufnr', null);
+                                $set('gernr', null);
                                 $set('machine_name', null);
                                 $set('characteristic_approver_master_id', null);
                                 $set('approver_type', null);
@@ -213,6 +215,7 @@ class RequestCharacteristicResource extends Resource
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
                                 if (! $state) {
                                     $set('aufnr', null);
+                                    $set('gernr', null);
                                 }
                                 $set('updated_by', Filament::auth()->user()?->name);
                             })
@@ -237,6 +240,9 @@ class RequestCharacteristicResource extends Resource
                                 return false;
                             })
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
+                                if (! $state) {
+                                    $set('gernr', null);
+                                }
                                 $set('updated_by', Filament::auth()->user()?->name);
                             })
                             ->default(function () {
@@ -246,6 +252,32 @@ class RequestCharacteristicResource extends Resource
                             })
                             ->readOnly(fn ($get) => ($get('item_id') == null))
                             ->disabled(fn ($get) => self::isFieldDisabled($get)),
+                        Forms\Components\TextInput::make('gernr')
+                            ->label('Serial Number')
+                            ->reactive()
+                            ->minLength(13)
+                            ->readOnly(fn (callable $get) => (! $get('aufnr')))
+                            ->afterStateUpdated(function (callable $set) {
+                                $set('updated_by', Filament::auth()->user()?->name);
+                            })
+                            // ->rules([
+                            //     function (callable $get) {
+                            //         return Rule::unique('class_characteristics', 'gernr')
+                            //             ->where('plant_id', $get('plant_id'))
+                            //             ->ignore($get('id'));
+                            //     },
+                            // ])
+                            // ->validationMessages([
+                            //     'unique' => "The 'GERNR' has already been taken.",  // The GERNR has already been taken for this plant.
+                            // ])
+                            ->required(function (callable $get) {
+                                $appTyp = $get('approver_type');
+                                if ($appTyp == 'Stop') {
+                                    return true;
+                                }
+
+                                return false;
+                            }),
                         Forms\Components\Select::make('machine_name')
                             ->label('Machine Name')
                             ->reactive()
@@ -333,6 +365,9 @@ class RequestCharacteristicResource extends Resource
                                     $set('current_value', null);
                                     $set('update_value', null);
                                 }
+                                if ($appTyp != 'Stop') {
+                                    $set('gernr', null);
+                                }
                                 $set('updated_by', Filament::auth()->user()?->name);
                             })
                             ->default(function () {
@@ -443,8 +478,9 @@ class RequestCharacteristicResource extends Resource
 
                                                     $plantId = $get('plant_id');
                                                     $jobNo = $get('aufnr');
+                                                    $sNo = $get('gernr');
                                                     $updId = $get('id');
-                                                    $pendingExists = RequestCharacteristic::where('plant_id', $plantId)->where('aufnr', $jobNo)->where('characteristic_name', $value)->latest()->first();
+                                                    $pendingExists = RequestCharacteristic::where('plant_id', $plantId)->where('aufnr', $jobNo)->where('gernr', $sNo)->where('characteristic_name', $value)->latest()->first();
 
                                                     if ($pendingExists) {
                                                         if ($updId && $pendingExists->id == $updId) {
@@ -966,6 +1002,11 @@ class RequestCharacteristicResource extends Resource
                     ->alignCenter()
                     ->searchable()
                     ->sortable(),
+                Tables\Columns\TextColumn::make('gernr')
+                    ->label('Serial Number')
+                    ->alignCenter()
+                    ->searchable()
+                    ->sortable(),
                 Tables\Columns\TextColumn::make('characteristicApproverMaster.machine_name')
                     ->label('Machine Name')
                     ->alignCenter()
@@ -1236,8 +1277,11 @@ class RequestCharacteristicResource extends Resource
                             ->label('Job Number')
                             ->placeholder('Enter Job Number')
                             ->numeric()
-                            ->minlength(7)
                             ->maxlength(10),
+                        TextInput::make('gernr')
+                            ->label('Serial Number')
+                            ->placeholder('Enter Serial Number')
+                            ->numeric(),
                         TextInput::make('work_flow_id')
                             ->label('Work Flow ID')
                             ->placeholder('Enter Work Flow ID'),
@@ -1313,7 +1357,7 @@ class RequestCharacteristicResource extends Resource
                     ])
                     ->query(function ($query, array $data) {
                         // Hide all records initially if no filters are applied
-                        if (empty($data['Plant']) && empty($data['machine']) && empty($data['item_id']) && empty($data['aufnr']) && empty($data['model_type']) && empty($data['work_flow_id']) && empty($data['machine_name']) && empty($data['request_type']) && empty($data['master_characteristic_field']) && empty($data['approver_status1']) && empty($data['approver_status2']) && empty($data['approver_status3']) && empty($data['approver_status']) && empty($data['created_from']) && empty($data['created_to'])) {
+                        if (empty($data['Plant']) && empty($data['machine']) && empty($data['item_id']) && empty($data['aufnr']) && empty($data['gernr']) && empty($data['model_type']) && empty($data['work_flow_id']) && empty($data['machine_name']) && empty($data['request_type']) && empty($data['master_characteristic_field']) && empty($data['approver_status1']) && empty($data['approver_status2']) && empty($data['approver_status3']) && empty($data['approver_status']) && empty($data['created_from']) && empty($data['created_to'])) {
                             return $query->whereRaw('1 = 0');
                         }
 
@@ -1339,6 +1383,10 @@ class RequestCharacteristicResource extends Resource
                             $query->where('aufnr', 'like', '%'.$data['aufnr'].'%');
                         }
 
+                        if (! empty($data['gernr'])) {
+                            $query->where('gernr', 'like', '%'.$data['gernr'].'%');
+                        }
+
                         if (! empty($data['model_type'])) {
                             $query->where('model_type', 'like', '%'.$data['model_type'].'%');
                         }
@@ -1436,6 +1484,10 @@ class RequestCharacteristicResource extends Resource
                             $indicators[] = 'Job No: '.$data['aufnr'];
                         }
 
+                        if (! empty($data['gernr'])) {
+                            $indicators[] = 'Serial No: '.$data['gernr'];
+                        }
+
                         if (! empty($data['model_type'])) {
                             $indicators[] = 'Model Type: '.$data['model_type'];
                         }