If the site is added properly

I had informed by Sitground adminstrator that in the last 72 hours there is an abnormally high number of simultaneous connections to the website:pharmacia1.com .
the siteground admins advise me to activate clould flare, now the admins told me that The Cloudflare service may not working properly despite the correct DNS records, the admins on siteground asked me to contact the Cloudflare support department and ask if your site is added properly.
I would like some help to ensure that the clouldflare is installed properly, or if there is any extra feature to help in DOS attack, shall I upgrade to solve this problem
thanks

Your site is working correctly via Cloudflare.

The Cloudflare dashboard has several things you can do without upgrading your plan. Look under the Security section, you can enable Bot Fight Mode, raise the security level, enable Browser Integrity Check, or even create specific firewall rules.