HORRIBLE XFINITY / COMCAST SERVICE

This is a terrible company with no online or phone complaint number - which tells you nothing will be resolved. I have called in 4 times. I set up a phone and internet service for my mother, who is 93, and during those 4 phone calls, we realized that I had received an old modem, and neither the sign-in name nor password worked. There is no one to give my 93 year old mother, who does not drive, a current modem that works. The worst part is that the installer was horrible and there is no way to send a complaint. He did not hook up mother's phone and didn't test the internet before he left. I have been on the phone for over 4 hours with Xfinity Tech support as there is no customer support. Tech support could not get the Internet to work at all - but I have a feeling it was the old model and not tech support.