My technician arrived today and installed Comcast in my home, but the router/modem I bought myself will not work. The technician's system stated that everything checks out on Comcast's end and there is something wrong with my SBG6580 router/modem. I can connect to it with devices via WiFi, but there is no access. I tried resetting the signal via the customer service on the phone, and a livechat rep tried helping me by showing me how to activate the service on my end. Nothing works. I heard I can PM my MAC address to an employee and they can make it work. How do I get my router to get internet access?