Install script creates the domain I don't need.

Hello!

I've used 2 different sytems to install single server Zextras CE instance: Rocky 8 and Ubuntu 22.04. With the rocky installation there was a problem from the beginning and I've reinstalled with Ubuntu. On the Rocky I had no any domain after the installation but on the Ubuntu I already have the domain I don't really need.Server name was zx.something.com and something.com domain was created. Can I safely create another global administrator and remove the domain created by the installation script? 

Thanks.