Event Type Code 4 OFDM/OFDMA errors MDD timeouts on multiple channels, repeated outages every couple of mins, VERY slow when available

For the last 2 weeks, my modem has been disconnecting every couple of minutes, and the speed when the connection is available is roughly 2 Mbps (I'm paying for 600 Mbps).

I had similar issues 6-8 months ago when after I replaced the entire wiring inside the home and replaced modem, router, etc, the Comcast technician found that the issue was with old wiring starting from the other side of the street. After he had fixed it, I was getting good speeds, up to around 480 Mbps for a few days (I didn't check speeds thereafter until recently).

However, this new repeated outage starting 2 weeks ago severely disrupts work. My Internet has been practically unusable for the last couple of weeks. A Comcast technician was scheduled for an appointment 8-10am today 12/19, but nobody contacted or showed up. I don't have constant connection to even complete a Comcast chat session to inquire about the no-show appointment or request a new appointment. Hence posting here, so I get some async help here.

Here's are the logs from my modem captured when I started typing this message a few hours ago. Been trying to send this out.