Hi,
I'm using a script to update the ip address and, everything working properly when update the domain record but I can't update subdomain record, for example:

mydomain.ddns.net --> Update OK
www.mydomain.ddns.net -> not updated.

FYI: I have a free account.

Kind regards,

The URL to update a subdomain looks like this:

http://api.dynu.com/nic/update?hostname=mydomain.ddns.net&alias=www&myip=[IP ADDRESS]&myipv6=[IPv6 ADDRESS]&password=[PASSWORD or MD5(PASSWORD)]

You can refer to the IP udpate protocol for more information.