diff --git a/packages/Webkul/Sales/src/Repositories/OrderRepository.php b/packages/Webkul/Sales/src/Repositories/OrderRepository.php
index f827cc219..aed17581d 100755
--- a/packages/Webkul/Sales/src/Repositories/OrderRepository.php
+++ b/packages/Webkul/Sales/src/Repositories/OrderRepository.php
@@ -206,7 +206,7 @@ class OrderRepository extends Repository
                 ->first() ?: false;
         }
 
-        $lastOrder = $this->order->orderBy('id', 'desc')->limit(1)->first();
+        $lastOrder = $this->model->orderBy('id', 'desc')->limit(1)->first();
         $lastId = $lastOrder ? $lastOrder->id : 0;
 
         if ($invoiceNumberLength && ($invoiceNumberPrefix || $invoiceNumberSuffix)) {
diff --git a/packages/Webkul/Sales/src/tests/sales/order/OrderRepositoryCest.php b/packages/Webkul/Sales/src/tests/sales/order/OrderRepositoryCest.php
index 96520ffef..3934f471e 100644
--- a/packages/Webkul/Sales/src/tests/sales/order/OrderRepositoryCest.php
+++ b/packages/Webkul/Sales/src/tests/sales/order/OrderRepositoryCest.php
@@ -15,7 +15,7 @@ class OrderRepositoryCest
         $this->repository = Mockery::mock(OrderRepository::class);
         $this->repository
             ->shouldReceive('generateIncrementId')
-            ->andSet('order', new Order);
+            ->andSet('model', new Order);
     }
 
     public function testGenerateIncrementIdOnEmptyDatabase(UnitTester $I)