1. Log into your cPanel account.
2.click on “Subdomains” Icon, In the “Domains” section
3. Under the “Modify a Subdomain” list you can see a list of subdomains.
4. Press on the “Manage Redirection” link that coincides to the subdomain which you would like to manage.
5. Beneath the “Subdomain Redirection” option you need to enter the link to which you want to change the subdomain in the available text box.