使用OpenResty安装whmcs之后，post提交的时候提示上游过早关闭连接

[user-jm4uwdaoirf]

提示了[error] 56#56: *580 upstream prematurely closed connection while reading response header from upstream, client: 54.255.238.62, server: xx, request:

[1Panel-huiwan]

有没有 WAF 或者其他的代理工具