Self-Signed SSL Certificate for Nginx in Ubuntu 16.04 And authorization (HTTP ERROR 403)

I have followed this link for self-signed ssl certificate for nginx.My nginx conf is like below:

server {
listen 80;
server_name myMachineIP;
return 302 https://$server_name$request_uri;

access_log /var/log/nginx/mysite.access.log;
error_log /var/log/nginx/mysite.error.log;
location / {
    proxy_pass http://127.0.0.1:8000;
    proxy_redirect off;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
location /static {
    alias /home/users/mysite/app/static;
}

}

server {

  # SSL configuration

   listen 443 ssl http2 myMachineIP;
   listen [::]:443 ssl http2 myMachineIP;
   include snippets/self-signed.conf;
   include snippets/ssl-params.conf;
}

But still I have

Access to 192.168.1.xxx was denied You don't have authorization to view this page. HTTP ERROR 403

What is wrong with this configurations? Any help would be appreciated.