on Friday, June 29 i lost internet access. On monday july 2, the tech said i need a new modem. The problem was caused by a comcast upgrade in my area (Atlanta GA). My modem no longer would be compatible. So i bought an Arris modem with dosci 3.1. connected, called comcast, put the new modem in my file, etc. no internet. called comcast. guy walks me through steps. no internet. he said go back in an hour, disconnect cables, shut down computer and modem turn everything back on. hour later, no internet. this morning did it again, i go internet. now my router had to be reconfigured to match modem after going through steps, internet disappears. powered down reboot. no internet but my router is fine. i can see netflix through dish/router. Iphone can surf with wi fi turned on. modem has two ethernet ports one connected to computer the other to router. What's up?