Short answer, you can't. As in your other topic, it is up to the ISP to do that. If this is a special case, you mihgt be able to get them to change it for you, but there is probably nothing you can do. I'm not sure how Optimum is for customer service, which is basically what it boils down to. The only other real way to be to get a new modem (or router, whatever whoudl change the physical adress that the DHCP server sees)
