I am having a very similar issue except i was getting about 240Mbps then services was disconnected. The disconnect was resolved with an incorrect billing issue. But when they went to reconnect an upgraded service the support agent had issues provisioning and activating the modem (same model C7000-NAS100). Finally we were able to get the modem activated but apparently the bootfile was now incorrect and speeds dropped to about 90Mbps. And the service rep could not get any new Bootfile successfully pushed to the modem claiming that t was because of non comcast gear. Which makes no sense because a few hours prior before disconnect speeds were over 240Mbps. So i asked to just be put back at the speeds we originally had ordered but the tier 2 support rep could not get Bootfile to load after sending reboot and refresh/provisioning signal to modem. Now the Bootfile is apparently stuck on Default and with upgrade should have been _Gigabit or what ever the original install service tech had set it to be. This is very frustrating because i had actually paid the bill about 2 hours before disconnect and now my service is all kinds of fracked up and nobody seems to have an answer to fix it. Also when i ask to just be forwarded to a team member for the back end to kindly help resolve this issue i am told there is no way to contact back end team. It seems to me that even though the support reps system say they are pushing the right configuration bootfile to my device it actually is incorrectly sending either invalid bootfile which then triggers the default settings or the comcast system is just sending the wrong bootfile. I really need help fixing this because my speed are half of what they were and no where near the Gigabit speeds i am paying for. A on site tech is scheduled to hep but first appointments that was open is a week away. I would like this cleared up in less than one week....
I can help with re-provisioning your modem. Please send me a private message verifying the first and last name of the account holder, and the street address or full account number associated with your services. To send a private message click on my name "ComcastChe", then click private message me and we can go from there.