My homestead site's not recognised by cloudflare

My homestead site shows as not secure. I have repeatedly attempted to secure it through Cloudflare as Homestead recommends, but Cloudflare doesn't recognise my web site address. It states to provide the root and not sub-domain. However, my site address is a sub-domain of homestead.com (it's 18 yrs old)!!
Please advise me ASAP as otherwise I'll have to cancel homestead's services. Thank you.