Assigning assets to a site

Hi guys,

We're tidying up and cleaning out our asset list and are trying to assign assets to particular geographical locations. We're pulling up all machines within a certain IP range (each site has a seperate IP range) and then in the asset search selecting all and clicking "Assign to site"

However, while the system reports "Resources Assigned to Site Successfully" the site field on the asset view has not changed, nor do the machines show up on a report run to show all machines in that site.

Is it possible to change the site a machine is in? We need this to track machines - ideally we want to set up the geographical location defined by the machine's IP, and then have it update if the machine moves to another site (and IP range)