接口：v3/ecommerce/account/cancel-applications【提交注销申请单】

提交body：

{"sub_mchid":"1641111732","out_apply_no":"D1641111732","application_info":[{"application_type":"SUB_CANCEL_ACCOUNT_APPLICATION","application_media_id":"V1_0orzY5HUSHXr_1eH5_X8gR4CQZHMHmMzL38xslmxC3ba_qA4Bpz6IaWxuhY8FfkxpPu_mC4ayGY64MhmltkZtQLJOzY9eQhmv6giwKWUAjk"}]}

返回错误：

Client error: `POST https://api.mch.weixin.qq.com/v3/ecommerce/account/cancel-applications` resulted in a `400 Bad Request` response:

{"code":"PARAM_ERROR","detail":{"location":null,"value":1},"message":"输入源“[/body/application_info/0]”映射到 (truncated...)

从报错看，其他参数都是正确的，签名也是没问题的，现在不确定是application_info这个参数哪里问题