Slow and freezing internet - XFinity

I have had slow and freezing internet for the last two months. I have complained and a technician came out and said it was because my modem was end of life. So I went out and bought a new modem that Comcast recommends. Still have the same problem. The technician spent less than 5 minutes, didn't check wiring which is very old. In fact wiring changed 12-13 years ago when HD became available. He used some phone and said everything was fine.

Also does anyone else have trouble when you go on yahoo with freezing up every time? You can't get someone on the line that speaks English could enough to understand and I don't trust anyone who calls and says they are a technician. Too many spam calls from Microsoft technicians. If I make the call I will give a Comcast technician the ability to access my computer but when they call me, how do I know they are a Comcast technician because they are all foreign just like the Microsoft spammers that call.

I have never had so much trouble with Comcast until 2-3 months ago when I changed plans. Comcast gives cheap rates to low in-come but for seniors you get nothing. We are on limited incomes too.