refill buyback

admin/control/refill_order_manual.php

@@ -628,7 +628,7 @@ class refill_order_manualControl extends SystemControl
         $input['after_available'] = ncPriceFormat($mem_info['available_predeposit'] + $params['mch_amount']);
         $input['admin_name'] = $admininfo['name'];
         $input['admin_id'] = $admininfo['id'];
-        $input['add_type'] = merchantModel::type_refund_back;
+        $input['add_type'] = Model('merchant')::type_refund_back;
 
         return Model('merchant')->addRefillEvidence($input);
     }