Recurring connectivity issues

In the past week and a half, I have been having a lot of connectivity problems to/from my Cisco DPC3941B gateway device..

I have a process set up externally to ping the gateway's public ip address and there have been a lot of times where the gateway is not pingable. When this occurs, internet access from the local network is not successful.

Looking in the event logs for the past week I see several instances of
2019/4/7 15:30:47 Notice [Dhcpc][1658]: erouter0 T1 Expired, Enter Renew State
and
2019/4/4 09:49:23 Critical [Docsis][566]: No Ranging Response received - T3 time-out

I've tried power cycling the modem multiple times but have not had much luck with things being any better.

Prior to this week, things were pretty solid for quite some time. The gateway feels pretty slow and sluggish when I am bumping around in the user interface too.

Here is a link to the logs from my external ping process to the gateway:

https://1drv.ms/b/s!AoA3H6TtNfIRhvZbilHR7EgA5CbWFQ

Notice the recent glut of ping failures.