update

app/Repositories/CmsContentTemplateSetRepository.php

@@ -341,6 +341,7 @@ class CmsContentTemplateSetRepository
         $res_id = implode(",", array_column($pro_array, 'product_id'));
 
         $product_key = config('constants.CMS_PRODUCTS');
+        $product_keys = '';
         if (isset($request['field_order'])) {
             $field_order = intval($request['field_order']);
             if ($field_order == 2){