Netgear Nighthawk RAX70 Can't Factory Reset?

We have a Neatgear Nighthawk RAX70 router at my parents' house. My brother, who doesn't live here anymore, set up the router a few years ago. It's been weeks since I asked him for the router login information, but he's busy and still hasn't sent it to me. It's annoying because he had a separate password (that he only knew) for one of the 5G bands, so now that band is just going to waste because we can't connect to it. I tried to do a factory reset to create a new login, but when the router finally booted up, nothing had changed. I also tried to do router password recovery, but I am not answering the security questions correctly. Is there some kind of security feature that doesn't allow the router to be factory reset? Or something I need to do differently?