Problems adding a subdomain

Hi
I just parked my domain (marianoalvarez.org) to my website and is working just fine. I added the subdomain “www.marianoalvarez.org”, which is also working fine. But when I try to add “m.marianoalvarez.org”, it says that the domain is already in use. Can anyone help me whith this?

Thanks in advance!

Can you create CNAME?

https://uk.godaddy.com/help/add-a-cname-record-19236

You can point a record to use as subdomain

i.e. point login to your site for login.yoursite.com to function?

I think I could, but it’s not quite I’m looking fore. I want a subdomain that is directed to an specific folder. I used to have it this way in my old hosting, so it should be possible. I only need to create a subdomain, but I can’t find how.

please tell me how can add my custom domain name to his server??

Follow this tutorial and use 000webhost nameservers to point your domain.