Sometimes people get back to us claiming that whenever they change something in their restored site, the original site changes as well and vice versa. The problem is that they didn't read the part of the manual regarding the restoration. As it is written in there, during the restoration you are presented with your database connection information. By default, ABI displays the parameters pertaining to your original (old, backed up) web site. However, you are restoring to a new server, or a subdomain in the same server. How can it ever be possible that you use exactly the same database information? It can't, because Joomla! stores all of the site's content (except media files) in the database. At the very least you have to use a different database table prefix, or an entirely different database. As a result you'll have to restore the site again, this time after reading the part on using the Akeeba Backup Installer. I'm sorry; there is no easier workaround to this problem.