Reverse DNS / PTR

Guys im looking for the correct way to add the reverse DNS to CF. We own the IP space and the domains are all registrered in CF. I see this page https://developers.cloudflare.com/dns/additional-options/reverse-zones/ however I dont have options to "create site" I have read that I need to email support etc. If someone can point me in the right direction or help that would be great. NE

Cloudflare Docs

Reverse zones and PTR records · Cloudflare DNS docs

If you control your own IP prefix(es), you can set up reverse zones with PTR records to allow reverse DNS lookups.