按照文档接入，https://developers.weixin.qq.com/doc/aispeech/platform/INTERFACEDOCUMENT.html，一直返回参数无效？

发送请求 POST json
{
    "query": "你好",
    "signature": "经过计算的签名"
}

{"err_msg":"invalid args","ret":-10,"msgtype":"unknow","query":"你好","rid":"50c71aca"}