What's the specific modem.no of your router? How about the lights on the router ? Is there any other devices that connected to the router with cable? It is suggested to simply your network topology,...

Hi Kwarren, Have you see a notice from tp-link here: http://forum.tp-link.com/showthread.php?101094-Security-Flaws-Severe-flaws-called-quot-KRACK-quot-are-discovered-in-the-WPA2-protocol

Hi Bishop Gregory Godsey, I see a notice here: http://forum.tp-link.com/showthread.php?101094-Security-Flaws-Severe-flaws-called-quot-KRACK-quot-are-discovered-in-the-WPA2-protocol Waiting for the...

So the service works in lan, it looks like it's related with the wan part. Maybe you can check if all the info from wan side is proper

They are both connected wirelessly, right? do you have the same issue on any other wireless clients like laptops, mobile devices? you may try to change the wifi channel on the cable modem router

the problem happens on 2.4G or 5G wifi? you may try to change the wifi channel and channel width