Scan New PC: still scanning using old IP address

I scanned one DHCP laptop earlier, then now it has another IP DHCP address since the location has been changed. Now I am trying to scan another laptop which happen to have same DHCP IP address which the other laptop used to be assigned. When I try to scan this new computer with hostname, it still pulls up the other laptop which currently has another IP. When I updated the laptop's IP at new location, I get an error message when I try to scan the new laptop:

FAILURE :One of the attribute of the Workstation refers another Object which does not exist. Hence cannot add this workstation.

Can you advice how I can scan this new laptop?