diff --git a/app/Http/Controllers/App/InventorySerialController.php b/app/Http/Controllers/App/InventorySerialController.php
index b61a161..46bf35e 100644
--- a/app/Http/Controllers/App/InventorySerialController.php
+++ b/app/Http/Controllers/App/InventorySerialController.php
@@ -76,6 +76,10 @@ public function store(Inventory $inventario, Request $request)
             'notes' => $request->notes,
         ]);
 
+        if(!$inventario->track_serials) {
+            $inventario->update(['track_serials' => true]);
+        }
+
         // Sincronizar stock
         $inventario->syncStock();
 
diff --git a/app/Services/ReturnService.php b/app/Services/ReturnService.php
index 56a5fb0..c1a332d 100644
--- a/app/Services/ReturnService.php
+++ b/app/Services/ReturnService.php
@@ -172,21 +172,21 @@ public function cancelReturn(Returns $return): Returns
         return DB::transaction(function () use ($return) {
             // Restaurar seriales a estado vendido
             foreach ($return->details as $detail) {
-                if(!$detail->inventory->track_serials) {
-                $serials = InventorySerial::where('return_detail_id', $detail->id)->get();
+                if ($detail->inventory->track_serials) {
+                    $serials = InventorySerial::where('return_detail_id', $detail->id)->get();
 
-                foreach ($serials as $serial) {
-                    $serial->update([
-                        'status' => 'vendido',
-                        'sale_detail_id' => $detail->sale_detail_id,
-                        'return_detail_id' => null,
-                    ]);
-                }
-                // Sincronizar stock
-                $detail->inventory->syncStock();
+                    foreach ($serials as $serial) {
+                        $serial->update([
+                            'status' => 'vendido',
+                            'sale_detail_id' => $detail->sale_detail_id,
+                            'return_detail_id' => null,
+                        ]);
+                    }
+                    // Sincronizar stock
+                    $detail->inventory->syncStock();
                 } else {
-                    // Restaurar stock numérico
-                    $detail->inventory->increment('stock', $detail->quantity_returned);
+                    // Revertir stock numérico (la devolución lo había incrementado)
+                    $detail->inventory->decrement('stock', $detail->quantity_returned);
                 }
             }
 
diff --git a/app/Services/SaleService.php b/app/Services/SaleService.php
index 66402e8..934f29a 100644
--- a/app/Services/SaleService.php
+++ b/app/Services/SaleService.php
@@ -49,7 +49,6 @@ public function createSale(array $data)
                     'quantity' => $item['quantity'],
                     'unit_price' => $item['unit_price'],
                     'subtotal' => $item['subtotal'],
-                    'serial_numbers' => $item['serial_numbers'] ?? null, // Si vienen del frontend
                 ]);
 
                 // Obtener el inventario