Prerender not detecting the token request

We have an angular app located at https://www.snark.art and we wanted to setup prerender by following Nginx code: https://gist.github.com/thoop/8165802

However in my prerender.io cached pages I see an error: We haven’t seen a request with your Prerender token yet.

We tried some suggestions but they did not seem to work.

Here is our code (Token removed):

worker_processes  1;

events {
    worker_connections  1024;
}

http {

    server {
        listen 4200;
        server_name  0.0.0.0;

        root   /usr/share/nginx/html;
        index  index.html index.htm;
        include /etc/nginx/mime.types;

        gzip on;
        gzip_min_length 1000;
        gzip_proxied expired no-cache no-store private auth;
        gzip_types text/plain text/css application/json application/javascript application/x-javascript text/xml application/xml application/xml+rss text/javascript;

        location / {
            try_files $uri $uri/ /index.html @prerender;
        }

        location @prerender {
            proxy_set_header X-Prerender-Token YOUR_TOKEN;
            set $prerender 0;
            if ($http_user_agent ~* "googlebot|bingbot|yandex|baiduspider|twitterbot|facebookexternalhit|rogerbot|linkedinbot|embedly|quora link preview|showyoubot|outbrain|pinterest|slackbot|vkShare||WhatsApp|Twitterbot|showyoubot|outbrain|vkShare|Slack-ImgProxy|Slackbot-LinkExpanding|Site Analyzer|SiteAnalyzerBot|Viber|Whatsapp|Telegram|developers.google.com/+/web/snippet/|redditbot|Discordbot|W3C_Validator") {
                set $prerender 1;
            }
            if ($args ~ "_escaped_fragment_") {
                set $prerender 1;
            }
            if ($http_user_agent ~ "Prerender") {
                set $prerender 0;
            }
            if ($uri ~* ".(js|css|xml|less|png|jpg|jpeg|gif|pdf|doc|txt|ico|rss|zip|mp3|rar|exe|wmv|doc|avi|ppt|mpg|mpeg|tif|wav|mov|psd|ai|xls|mp4|m4a|swf|dat|dmg|iso|flv|m4v|torrent|ttf|woff|svg|eot)") {
                set $prerender 0;
            }

            #resolve using Google's DNS server to force DNS resolution and prevent caching of IPs
            resolver 8.8.8.8;

            if ($prerender = 1) {
                #setting prerender as a variable forces DNS resolution since nginx caches IPs and doesnt play well with load balancing
                set $prerender "service.prerender.io";
                rewrite .* /$scheme://$host$request_uri? break;
                proxy_pass http://$prerender;
            }
            if ($prerender = 0) {
                rewrite .* /index.html break;
            }
        }
    }
}

Source: AngularJS