How to rename my domain?

Unfortunately, it is not possible to rename a domain. You can only change/replace it with another domain name.

joomla site customers can do this following the instructions below:

• Order a new domain. This can be done from your User Area -> Add Services tab.
• Change the primary domain name of your account. This can be done from your User Area -> My Accounts -> Manage (next to the hosting account whose primary domain you wish to change) ->  Change Primary Domain.
  

Related Article

destination source:https://www.siteground.com/kb/how_to_rename_my_domain/