Deco network issues

Good day. I am having issues connecting to websites when I use a particular ISP. When I do speedtests, ookla says there is a socket error. The connection error come and goes. Sometimes everything is fine and other times websites don't load. I've been having this issue for a couple of months. I've had the system for a couple of years and never had issues like this before.
There are no issues when my PC is directly connected to the modem router. I also have a backup ISP and there are no issues using my network with the backup.


@TP-Link