微信使用了单品优惠卷后进行部分退款时，一直报错“微信商品编码非法”？

1. 支付传递的detail参数：,"detail":{"cost_price":102,"receipt_id":"","goods_detail":[{"goods_id":"118902","wxpay_goods_id":"","goods_name":"","quantity":1,"price":101},{"goods_id":"118902213","wxpay_goods_id":"","goods_name":"","quantity":1,"price":1}]}

2. 支付时使用了一个满1.01减1块的单品优惠卷，用户实际付款0.02元，

3. 现在我要进行部分退款，退掉goods_id=118902 的商品，退款传递的参数：<xml><appid>*************</appid><detail><![CDATA[{"goods_detail":[{"goods_id":"118902","wxpay_goods_id":"","goods_name":"","refund_amount":101,"refund_quantity":1,"price":101}]}]]></detail><mch_id>*************</mch_id><nonce_str>68997111441454668597289644171432</nonce_str><out_refund_no>2019091016372626781448111</out_refund_no><out_trade_no>201909101631SHWX6272552001</out_trade_no><refund_fee>101</refund_fee><total_fee>102</total_fee><transaction_id>4200000377201909107405698028</transaction_id><sign>*************</sign></xml>。                                                                                                                                                                 微信响应的结果是：<xml><return_code><![CDATA[SUCCESS]]></return_code>\n<return_msg><![CDATA[OK]]></return_msg>\n<result_code><![CDATA[FAIL]]></result_code>\n<err_code><![CDATA[PARAM_ERROR]]></err_code>\n<err_code_des><![CDATA[微信商品编码非法]]></err_code_des>\n<appid><![CDATA[*************]]></appid>\n<mch_id><![CDATA[*************]></mch_id>\n<nonce_str><![CDATA[zCp3I0y9xopOo79q]]></nonce_str>\n<sign><![CDATA[*************]]></sign>\n</xml>  ,请问这个是为什么？无论我怎么退款，怎么调整金额，调整退款商品明细，依然都是这个错误提示？