It appears that ISPconfig created an alias that rewrites firstname.lastname@example.org to
email@example.com, but I think it should be "firstname.lastname@example.org". Is there a place in ISPConfig to fix this.. or do have to fix the alias individually?
There is nothing wrong with that, its the intended behaviour. Make sure that ubuntu.elatia.net is set in DNS or the local hosts file to point to your server.