Go to subscribenet, check in that license, and then generate a new one based on the hard drive id. The lmtools utility in the SySam folder will tell you what the hard drive ID is that you want to use.
The problem is that by default Sysam uses the primary network card. The issue with laptops is that tends to change if you switch between an onboard ethernet card, a wireless card, and perhaps no connector at all when mobile and not in range of a hot spot. By basing the license on the hard drive ID rather than the network card you avoid the confusion.