https://api.mch.weixin.qq.com/mmpaymkttransfers/querycouponsinfo <xml> <return_code><![CDATA[SUCCESS]]></return_code> <result_code><![CDATA[FAIL]]></result_code> <err_code><![CDATA[INVALID_REQUEST]]></err_code> <err_code_des><![CDATA[270077955]]></err_code_des> </xml>