Nginx SSL wrong version number 求解

各位大佬，昨天配置了一个 CHATGPT WEB 项目玩了玩，本地 http://localhost:8855 可以正常使用，于是想配合 nginx 反代出来，让自己在外面也能用一下。但是 nginx 一直报 502 错误。具体报错内容是 chatgpt 项目是 https://github.com/CODEisArrrt/chatgpt-dark

[error] 1019768#1019768: *9 SSL_do_handshake() failed (SSL: error:1408F10B:SSL routines:ssl3_get_record:wrong version number) while SSL handshaking to upstream, client: 39.xx.xx.xxx, server: aaa.bbb.com, request: "GET / HTTP/1.1", upstream: "https://192.168.50.49:8855/", host: "aaa.bbb.com:6053"

Nginx 的 conf 字段如下

server { listen 6053 ssl http2; server_name aaa.bbb.com;

ssl_certificate /etc/nginx/cert/nginx-crt.pem;
ssl_certificate_key /etc/nginx/cert/nginx-key.pem;
client_max_body_size 1024m;


index index.html;
error_log      /var/log/nginx/error-chatgpt.log error;

location / {
    proxy_pass https://192.168.50.49:8855;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_read_timeout 43200000;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header Host $http_host;
    proxy_set_header X-NginX-Proxy true;
    proxy_buffering off;
}

}

同样的 conf 内容，Nginx 的其他 web 服务都正常。证书是 acme.sh 做的自签证书且在有效期内

检索过相关网页，但是都没有太多作用，尝试过删除 http2 但是没有作用

请问我这个报错该如何 debug