Frequent internet disconnection

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Also, here are the error messages: 

Hi and thank you for writing back. The tables are below. I will see if they are different in the evening. Also, I forgot to mention, my computer is connected via ethernet cable to my router / this is not a wi-fi issue. 

Downstream:

Channel / Lock Status / Modulation / Channel ID / Freq. (MHz) / Pwr (dBmV) / SNR (dB) / Corrected / Uncorrected

Upstream

This happens to us too. Our internet goes out probably 10-15 times per day, down from 20-30 with the "new" modem that we were sent. I was told they would send us an upgraded version of the modem but it is exactly the same as the old one. If they say that you need to switch to an Xfinity modem, you don't. The service is trash either way. If there was any other internet provider where we live, I would have switched a month ago when we signed up. This is the worst service I have ever had and their customer service is a joke. They never have real solutions and avoid a real fix. So sorry you're dealing with this too. It has made working from home a nightmare for me.

thanks. I wholeheartedly agree with you regarding the xfinity modem. If they tell me that's what I need then I'll go to a different provider; I fortunately have a choice (although unclear if any of the others are better). 

update: after several days of surprise stability, this problem recurred. I got on a chat with Xfinity -- and after my internet went out during the chat -- they seem to believe the problem has been solved. There troubleshooting said "there was corrupted data within the network and needed a refresh." the agent was unable to provide any more useful information. 

Further updates:

while xfinity's solution worked for a few days, once again the problem recurred

Chatting with them tonight they said, "since I am synchronizing all the settings on your modem so that it will be fully functional and fully operational. I successfully updated all the settings on your modem so that your internet connection will be stabilied into our system." 

I am doubtful this will work but will hold out a little hope

A neighbor posted to Nextdoor saying that when they talked to Xfinity (after trying 3 separate modems), Xfinity finally revealed to them that our node routinely operates at >85% capacity, which is why their internet has been unstable. They have not yet revealed this to me. 

There is probably a loose and/or corroded cable connection somewhere - maybe inside your house - maybe at the "demarc" outside your house - maybe somewhere beyond your demarc underground or on a pole or in one of those grey boxes by the side of the road.   

As far as I understand, every cable connector exposed to varying heat and humidity will inevitably loosen itself and corrode, requiring replacement and/or "cuttting cable nd re-crimping a new connector".

The timing of the failure is a clue as to whether the problem is HEAT or MOISTURE.

When failures occur dusk/nighttime that is when the cables/connectors are cooling and condensation will form, increasing impedance to the signal.       Problem in this case is MOISTURE along with temperature-cycling.  Tighten the connectors but note that the fix will be temporary at best - connection will require recrimp and new connector if any moisture/corrosion is visible whatsoever. 

When failures occur daytime/sunlight that is when cables/connectors are HOT and impedence increases.  Problem in this case is hopefully just the temperature cycling - if no moisture the connectors will not be corroded they will merely be LOOSE.  Tighten them.

It's always worse in summertime.