"appId":"wx8a8b051a1cf02218","timeStamp":"1626405067","nonceStr":"5k9cd89jrpvt2ytl38s3ug5ynar5ic7t","package":"prepay_id=wx1611110785294346b4e75c642cdb6b0000","signType":"RSA","paySign":"SxsWsohGASr0VAGMmYDLY7uim8RCy5QF5UJ160PvgnLK2qnj61\/zNhPyaj3HRABjRR02nbps5t00nWJ3nXcpDbMOPrz9VrKjEPI53SxlHM2+r1BsBE5ciT2bVn1W1bPQGjJ6vOHfw\/eI3fBfJBiSEX0PosEXw+Xh\/rZPLP7Xthz6Q8nEOxfVzXwFSxpxFTqTyNZNFvuexO12boe+ENOpVrR7uaXo2sCu3snyHKNHYIKY64mkJ\/2GdLjLN10tp42BGq+mhirqcnlmymd7O4WhZ1bvux\/3gBHxn8mTllPSXWFB2TlVoyufufc8B1lNwIXxEaniFn\/L\/aNEWVq9I3XF9A=="

这里区分两种情况,第一种是小程序是服务商的,第二种就是小程序是子商户的。
按你描述,小程序应该是子商户的,这种情况下,sub_appid是必传的,sp_openid不传,传sub_openid,也就是小程序获取到对应用户的openid,调起支付的appid也是传小程序的。
你的调用对应关系:
我是服务商模式的
一定是你传错了。
前端调起支付的 AppId 和后端调微信商户接口下单时的 AppId 要一致,不能是后端用公众号下单、前端用小程序调起这种。
另外你确定这个 AppId 是小程序的吗?
"sp_appid":"wx8a8b051a1cf02218","sp_mchid":"1606143582","sub_appid":"","sub_mchid":"1607958659","description":"\u5b9e\u7269\u8ba2\u5355_100679752631045042","out_trade_no":"100679752631045042-mini","time_expire":"2021-07-16T13:10:31+08:00","attach":"product_buywxpay_jsapi","notify_url":"https:\/\/shop.codechain.shop\/cmobile\/api\/payment\/xcx_jspi_v3\/notify_url.php","goods_tag":"","settle_info":{"profit_sharing":true,"subsidy_amount":0},"amount":{"total":4900,"currency":"CNY"},"payer":{"sp_openid":"o4baQ0njOxeXDO4yZ0fPXH3lgkuc","sub_openid":""