C7000v2 wifi slow after reboot

[ejbolden]

Short story, I unplugged the power to my modem/router combo (C7000v2) to reboot it and get the new speed that Xfinity said I would have (400mbps).  After plugging it back in and letting the router come back to life, my wifi speeds are ridiculously slow.  My 2ghz is maxing out at around 20mbps and my 5ghz is lucky to see 2mbps.  I plugged my computer into the back of the router and wired it is outputting the full 400mbps.  I've tried rebooting the router from the app multiple times, unplugging it and plugging it back in all to no avail.  Completely lost on what could have happened, hopefully someone here has some ideas.

[plemans]

They might have messed up something in the re-provisioning. 

Have you tried a simple factory reset? 

Sometimes clearing out the old settings can help when you upgrade services. 

[ejbolden]

So I tried restarting the router. Pushed the button on the back, went in the app and re-added it. Went through the whole setup again and made my wifi names and passwords. My 2g is not up to 40mbps, 5g is still sitting pretty at 0.7mbps….. while plugged into the Ethernet is over 400. Im at a loss, this all started with me just unplugging it and plugging it back in.

[plemans]

have you tried changing the wireless channels used?
Also, try different devices

[ejbolden]

I did not (and never would have thought of) changing the channels on the router! Clicked a random 100 for the 5g and now I’m getting 290mbps! Going through the channels one by one to find the fastest speeds, unless there’s a better way lol.

Thank you so much for the help! Not sure what changed from unplugging to replugging this in that my wifi went to garbage, but glad I was able to get it back with some help!