2.4gh Stopped working

Try hard resetting the device to factory defaults by pressing and holding in the recessed reset button on the rear for 30 seconds. This can sometimes clear up some weird behavior issues. You will lose any customized settings, and they will need to be re-configured from scratch. Good luck !

I had the same thing happen today with the same individual wifi setup.

When I tried to connect with my phone it kept saying "Authentication Error Occured".

I logged into the router Admin Panel through the web browser and clicked on the Troubleshooting menu on the left side and then selected the  WiFi Spectrum Analyzer.

I noticed a large number of routers around me in other houses were using Channel 6 for their 2.4ghz frequency. I went into the Wifi Setup in the admin panel and changed the Channel Setup from Auto to Manual. Then I changed the frequency from 6 to 9, which had the least number of routers on that channel. I saved the changes and waitied for the router to refresh the changes. I got on my phone and did a Forget Network on my 2.4ghz network and then reconnected and entered my password. The new channel did the trick! Confirmed it with my laptop as well. My 2.4ghz network was back up and running.

So it could be that your router didn't just drop your 2.4ghz network. It could be that the channel is just too crowded, just like your car bluetooth transmitter when you are trying to find a radio station to connect to so you can stream your music from your phone.

Good luck!

I have the same problem on occasion. Restarting the router by unplugging it does not fix the issue. I have found if I log into my Xfinity app and restart my my gateway from the app it fixes the issue. Hope this works for others😊