Orbi won’t reset password. Error 400.

I wanted to log in to my router but I don't know the password. Generally I use the Touch ID on the app but I tried it from the browser.

I went through the reset procedure, entering the serial number and answering the security questions then I just get an error 400 page telling me the operation is not supported. I would have thought it should support resetting a password so it's broken in some way.

Now, it's also preventing me from logging in with the app too so I have no way to access my router.

I see some threads on here suggesting that basically I need to reset it. Hardly ideal - is that really the only option?

What do I lose by doing that? What about BitDefender? Will I lose that? Is there any danger it will get bricked and I'll just see that error during setup? At least it lets me connect to the internet right now.

Thanks