Intermittent outages; otherwise quite good!

At my old house, my modem worked for many years. I moved in March, and the service is very bad. I can go to http://192.168.100.1 and view the connection strength. I wrote a script to do that every ten seconds. All four downstream channels are present. A typical section of the graph looks like this: https://i.imgur.com/ZeNWKVL.png . That straight part of the line around 5 (dBmV) is solid internet access. I sometimes get that for 10 or 12 hours some days. The part that looks like garbage results in an outage. To me, the pattern looks like a loose connection. In our cul-de-sac, there are roughly 8 houses. Four or so of them have rock-solid internet and are very happy (one of them pay s for gigabit connection and everything is great). I have a second modem and have tried using that, but I get the exact same quality of service.

There is a "drop" (for lack of a better word?) between me and my neighbor's house. Inside it is my and my neighbor's connection terminals. He and I have the exact same experience: intermittent connection issues. No timing, just sometimes works, sometimes doesn't.

How do I get it fixed? I have called Comcast. They say "We see that your connection status is red and not working properly. We can't do anything for you.". I guess they're scared of getting COVID from me if they come out? I really would hate to switch to DSL as I have enjoyed using comcast in the past, but I'm not sure how to get comcast to fix this problem.