西班牙英国宫百货退税

在西班牙英国宫百货买东西退税，我选的是退款到信用卡，除了邮寄退税单还要寄原始发票吗？我只寄了退税单,过了10天也没收到钱，写信问了，答复如下。而且下文里提到还要在原始发票上盖海关章，海关章不都盖在退税单上了？无法理解阿，有经验的童鞋帮我看看吧，先谢谢了

Dear Customer,You should send us the original invoice with the customs stamp in the business reply envolope you were given. If you do not keep it, this is our address:EL CORTE INGLESDEPARTAMENTO ADMINISTRACION VENTASC/HERMOSILLA, 11228009 MADRIDESPAÑAIf the purchases were paid in cash, we will send you a nominative bank cheque to any address you provide. If they were paid with a credit card and it is not stated in the invoice, you may send us a letter providing the full number of an international use credit card VISA, MASTERCARD, DINNERS, AMERICAN EXPRESS and its expiry date.