Domain mapping is not working giving error of Cname records

Domain mapping is not working giving error of Cname records

Hi 
I have created subdomain with A record with my server IP Address as support.website.com
created Cname record like in Host I have given my Subdomain name and Points to desk.cs.zohohost.com
when I am trying to map my domain in zoho desk it is giving error of Cname.
Please help me where I have done wrong?
Thanks.