nginx不能代理delete请求

两台服务器

A(阿里云)   运行nginx（版本：1.20.1）

B(华为云)   运行后台服务

浏览器访问时get，post请求都正常，delete请求就出错？哪位大神知道怎么回事？

修改nginx配置文件：

location /aaa {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Credentials' 'true';

dav_methods PUT DELETE;

if ($request_method = 'OPTIONS') {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Methods' 'GET, POST,PUT,DELETE,OPTIONS';

add_header 'Access-Control-Allow-Headers' 'Authorization,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';

add_header 'Access-Control-Max-Age' 3600;

add_header 'Content-Type' 'text/plain charset=UTF-8';

add_header 'Content-Length' 0;

return 204;

}

if ($request_method = 'POST') {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Methods' 'GET, POST,PUT,DELETE,OPTIONS';

add_header 'Access-Control-Allow-Headers' 'Authorization,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';

}

if ($request_method = 'GET') {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Methods' 'GET, POST,DELETE,PUT,OPTIONS';

add_header 'Access-Control-Allow-Headers' 'Authorization,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';

}

if ($request_method = 'PUT') {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Methods' 'GET, POST,PUT,DELETE,OPTIONS';

add_header 'Access-Control-Allow-Headers' 'Authorization,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';

}

if ($request_method = 'DELETE') {
add_header 'Access-Control-Allow-Origin' '*';

add_header 'Access-Control-Allow-Methods' 'GET, POST,DELETE,PUT,OPTIONS';

add_header 'Access-Control-Allow-Headers' 'Authorization,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';

}

proxy_pass http://aaa/aaa;

proxy_set_header Host $host;

proxy_set_header X-Real-IP $remote_addr;

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

}