Change IP

[geeklandhosting.com]

Ok so I added the new hostname and IP address, the only problem is when I try to delete the old one it says that I have resellers assigned to that address, so I tried to change the reseller to be on the new address/hostname. I said it couldn't because I had clients that were using that address. So I assigned both of them to the reseller, thinking i could just go into the user or reseller and change the client assignment. I could not find this option. I am at a loss. There has got to be a better way, I have a few resellers and a lot of users, this would be really time consuming.
Thanks in advance for any help...

JCannon