I had set up a small business with this Archer C3150 router years ago, and it worked fine - but recently, I had to change to a wired-only Cisco router to accommodate a change to a new phone provider. The C3150 didn't meet the security requirements for the new provider.

So I repurposed the C3150 as an access point. That works fine except for the guest Wi-Fi - which no longer works. It's not too surprising since this device isn't "routing" anymore. I've disabled the guest's WiFi. Is there any way I can re-enable the guest's Wifi so that it works again?