Your Arlo network is broadcast by Arlo base station. If you have a smart Arlo base station, you'll in fact get two: one for 2.4GHz and the other for 5GHz. You can neither switch it off, nor log into it/them. The Arlo network is used to communicate with your cameras and since Arlo is a closed system, there is nothing you can do about it.
To deal with your other problem: reset the router. Although I'm confused why and how it would try to log into Arlo. And if the issue are your devices trying to connect to Arlo, you need to reset their networking settings or choose 'forget' that network.
