Recreate a scope in DHCP Server.

Recently I’m tried to recreate a scope in DHCP Manager. But When I type in the start address and end address, I got this message, “The specifed range either overlays with an already existing range or is invalid.” The way I did is delete the orginal scope, then go to -scope/create. Is it I need to stop the DHCP Server first??? If you know anything about it, I’ll be happy to know them! Thanks!