diff --git a/app/Filament/Imports/GrMasterImporter.php b/app/Filament/Imports/GrMasterImporter.php
index 8540a0ec..40e35c0a 100644
--- a/app/Filament/Imports/GrMasterImporter.php
+++ b/app/Filament/Imports/GrMasterImporter.php
@@ -10,6 +10,7 @@ use Filament\Actions\Imports\Exceptions\RowImportFailedException;
 use Filament\Actions\Imports\ImportColumn;
 use Filament\Actions\Imports\Importer;
 use Filament\Actions\Imports\Models\Import;
+use Filament\Facades\Filament;
 use Str;
 
 class GrMasterImporter extends Importer
@@ -67,6 +68,8 @@ class GrMasterImporter extends Importer
         $plant = null;
         $item = null;
 
+        $userName = Filament::auth()->user()?->name;
+
         if (Str::length($plantCod) < 4 || ! is_numeric($plantCod) || ! preg_match('/^[1-9]\d{3,}$/', $plantCod)) {
             $warnMsg[] = 'Invalid plant code found';
         } else {
@@ -94,26 +97,38 @@ class GrMasterImporter extends Importer
             $warnMsg[] = 'User not found';
         }
 
-        if (! empty($warnMsg)) {
-            throw new RowImportFailedException(implode(', ', $warnMsg));
-        } else { // if (empty($warnMsg))
-            $grMaster = GrMaster::where('plant_id', $plant->id)
-                ->where('serial_number', $this->data['serial_number'])
-                ->latest()
-                ->first();
+        $serialExists = GrMaster::where('plant_id', $plant->id)
+            ->where('serial_number', $this->data['serial_number'])
+            ->first();
 
-            if ($grMaster) {
-                throw new RowImportFailedException('Serial number already exist!');
-            }
+        if ($serialExists) {
+            $warnMsg[] = 'Serial number already exists for this plant!';
         }
 
-        GrMaster::updateOrCreate([
-            'plant_id' => $plant->id,
-            'item_id' => $item->id,
-            'serial_number' => $this->data['serial_number'],
-            'gr_number' => $this->data['gr_number'] ?? null,
-            'created_by' => $this->data['created_by'],
-        ]);
+        $grNumberExists = GrMaster::where('plant_id', $plant->id)
+            ->where('gr_number', $this->data['gr_number'])
+            ->first();
+
+        if ($grNumberExists) {
+            $warnMsg[] = 'GR Number already exists for this plant!';
+        }
+
+        if (! empty($warnMsg)) {
+            throw new RowImportFailedException(implode(', ', $warnMsg));
+        }
+
+        GrMaster::updateOrCreate(
+            [
+                'plant_id'      => $plant->id,
+                'gr_number'     => $this->data['gr_number'] ?? null,
+                'serial_number' => $this->data['serial_number'],
+            ],
+            [
+                'item_id'    => $item->id,
+                'created_by' => $userName,
+                'updated_by' => $userName,
+            ]
+        );
 
         return null;
         // return new GrMaster();