How To Setting Subdomain Without Domain (.com)

[wehaye]

I have read and follow the tutorial on the following links related to setting subdomain without domain.
http://docs.sentora.org/?node=50

The way it works when I have a subdomain with tld = dot com (.com). Example: test.domain.com
But when I add a subdomain using a domain that ends other than .com, for example dot software (.software) -> test.domain.software, then I get the following error message:
You can not add a Sub-Domain here. Please use the subdomain manager to add Sub-Domains.

Please help from the seniors and the master here.
What should I do?

Thank you very much.

[Xversion]

Hello,

Instead of creating the Sub Domain of 'test.domain.software' in your Sub Domains do the following:

Go to Domains -> Add Domain of 'test.domain.software' there directly.

Here is a graphical tutorial:

[wehaye]

I also did the same thing as you demonstrated.
the result is still the same.
there is an error message like the following:
"You can not add a Sub-Domain here. Please use the subdomain manager to add Sub-Domains."

Anyway, I installed sentora panel using the same domain, more precisely is panel.domain.software.

Then I tried to add a sub domain test.domain.software, then I get the error message as mentioned above.