how to resolve with weak signal from comcast router?

I believe that is an unusual circumstances of our move into Brookline MA from Warrington PA.

We had and still have a  Comcast Internet service in PA and order a cheaper Internet NOW,

And now we have 2 problems:

To get a customer service we need to be together cause I am a primary user in PA but my wife is a primary user in MA

secondly I have on my PC which I use a lot very unstable and weak signal from Internet NOW router,

Please help to resole the issues!