If the issue is with ip lease of the modem, then you can try following.
1.Open router config page. (192.168.1.1) or
www.routerlogin.net/basicsetting.htm
2.username= virgin, Password= password
3.Scroll down and look for router mac address.Select the option "use computer mac address".
4.Power cycle modem and router in sequence.
I hope this helps....:-)