PHP 支付宝退款 "ACQ.INVALID_PARAMETER" 参数无效

官方文档说有的参数是可选的，一开始我把大部分都删除，结果  "ACQ.INVALID_PARAMETER" 参数无效

其实

.
"\"operator_id\":\"OP001\"," .
"\"store_id\":\"NJ_S_001\"," .
"\"terminal_id\":\"NJ_T_001\"" .

这几个参数是不能删的，后来我直接在官方文档复制上去

    "{" .
    "\"trade_no\":\"".$dataPa->trade_no."\"," .
    "\"refund_amount\":".$dataPa->amount."," .
    "\"refund_reason\":\"正常退款\"," .
    "\"operator_id\":\"OP001\"," .
    "\"store_id\":\"NJ_S_001\"," .
    "\"terminal_id\":\"NJ_T_001\"," .
    "  }"

这样子提交还是出现了同样的错误，后来才注意到最后一个参数不能带逗号“,”的

    "\"terminal_id\":\"NJ_T_001\"" .