Nginx - SignalR Web socket Connection Error: Error: WebSocket failed to connect. 500 internal server error

Question

UI:

const connection = new signalR.HubConnectionBuilder()'       .withUrl("https://example.com/chatHub", {
          skipNegotiation: true,
        transport: signalR.HttpTransportType.WebSockets,
      })

Backend:

` services.AddSignalR(options =>`
` { options.EnableDetailedErrors = true; });``services.AddCors(options =>` `{`
               ` options.AddPolicy("CorsPolicy",`
    ` builder => builder`                           `AllowAnyMethod()`
`                                .AllowAnyHeader()`
 `                               .SetIsOriginAllowed((host) => true)`
`                                .AllowCredentials());`
 `           }); }`

`app.UseEndpoints(endpoints => { `     
`     endpoints.MapHub<ChatHub>("/chatHub", options =>`
                `{ options.Transports =`
                        `HttpTransportType.WebSockets |`
`                        HttpTransportType.LongPolling;            });`
            
`      app.UseCors("CorsPolicy"); `
 `     app.UseWebSockets();`

Nginx:

`ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
  ssl_prefer_server_ciphers off;

` map $http_connection $connection_upgrade {`
 `           "~*Upgrade" $http_connection;`
`            default keep-alive;`
 `       }`

       upstream my_app{
               ip_hash;
               server localhost:5000;
       }

        server{
                listen 443 ssl;
                server_name example.com;

                ## SSL Configurations
                ssl_certificate /etc/letsencrypt/live/example.com/cert.pem;
                ssl_certificate_key etc/letsencrypt/live/example.com/privkey.pem;
                include /etc/letsencrypt/options-ssl-nginx.conf;
                ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

                ##Configure the SignalR endpoint
                location / {
                        proxy_pass https://example.com/chatHub;

                        # configure Websockets
                        proxy_http_version 1.1;
                        proxy_set_header Upgrade $http_upgrade;
                        proxy_set_header Connection $connection_upgrade;
                        proxy_cache_bypass $http_upgrade;
                        proxy_set_header Connection $http_connection;
     # Configuration for ServerSent Events
                       proxy_buffering off;

                        # Configuration for LongPolling
                       proxy_read_timeout 100s;

                        proxy_set_header Host $host;
                        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                        proxy_set_header X-Forwarded-Proto $scheme;
                }