Our site was working fine. But suddenly I am unable to connect to Wordpress wp-admin account. I keep hitting 521 server error. Our site is hosting on cloudflare only. My website name in www.localfobs.com.
Most likely not. Cloudflare does not host WordPress sites (or any other PHP-based site). Cloudflare just proxies traffic between visitors and your actual host.
A 521 error happens when Cloudflare is unable to make a TCP connection to your origin server. Review the suggestions in this Community Tip for Quick Fix Ideas.