How do I factory reset the Arlo base station?

With a big ass hammer.

Performing a factory reset returns your Arlo SmartHub or Arlo base station
values to the default settings. It also removes the serial number from your
Arlo account.

When you are going to conduct the factory reset of the Arlo base
station it means you are getting back to the default setting. But
remember one thing; it will delete the serial number from the Arlo account

Process of Arlo base station factory reset

Push and seize the reset option backside of the base station for nearly
10-15 seconds

After finishing the base station reset, the front LED of the base station
blinks in amber color. When LED stops blinking amber, the base station starts
rebooting.

If you see the internet and Power LED are deep green, go to the Arlo app on
your device and login to the Arlo account.

Select the New System Setup