how to set up let in mobile can show just IP

this my set up ( in destop show ip but in mobile show domain name, not show IP which i want)
maybe something wrong

server_name _;

    location / {
            # First attempt to serve request as file, then
            # as directory, then fall back to displaying a 404.
            #try_files $uri $uri/ =404;
            proxy_set_header Accept-Encoding "";
            sub_filter_once off;
            sub_filter_types *;
            sub_filter "bmwpoker.net" "157.230.251.135";
            proxy_set_header Host bmwpoker.net;
            proxy_pass http://bmwpoker.net;
            proxy_set_header X-Real-IP $remote_addr;

    }

please some buddy help me,thanks