DNS WPML - subdomain settup

as a user of the WPML multilingual plugin, I am looking to create subdomains of my main domain to distinguish the languages. When I create a subdomain with the A field or the CNAME field, cloudflare took me to a page which asks me to modify my configuration which I do but nothing works.
Here is the message I received:
What happened?
You’ve requested a page on a website (fr.xx.com) that is on the Cloudflare network. Unfortunately, it is resolving to an IP address that is creating a conflict within Cloudflare’s system.

What can I do?
If you are the owner of this website:
you should login to Cloudflare and change the DNS A records for fr.share-natural.com to resolve to a different IP address.

Any help?

Which host are you using, and have you followed their tutorial on adding custom domains?