Hi,
My website is down with a error message 521. I had the website set up by someone and he set the website up with cloudflare hosting it, i have no log in details. The error message says web server down. Please can you help me as my company website is no longer working. Its says contact cloudflare to fix the issue. Please can you fix this for me ASAP.
Welcome to the Cloudflare Community. 
Even on the most expensive plans Cloudflare is very much a self-service platform. This means that while the Community can help you find the right direction, you will need to take the action required to achieve your desired results.
Cloudflare is not likely hosting your website. Cloudflare is a security and performance platform that operates between your website and your vistors. If you click the 521 in your post or here in my reply, you will be taken to a Community #tutorial that lists items to check. The problem you describe is likely with the webserver that hosts your site. You will need to find out who that is. The party that set it up wild be the best place to start.