Unexpected problem with a new Asus RT-AX58U V2

[ajay11]

I am familiar with Asus routers for a long time, know everything about their setup and UI.
But when I bought this new 58U, I cannot bypass it's QIS page as usual (over LAN cable). None of the standard ways of getting past the QIS page work. The pages 192.168.0.0 or .1.1 or .50.1 ... /index.asp do not work. After a factory reset one is asked to replace admin/admin as credentials, but whatever one enters, is is ignored during next login and you end up on the QIS page again. The user manual is useless, it only knows about QIS too.
For my purposes the more "automated" setup options (QIS, with QR code and all the rest) do not help and do not work. I need access to the UI.
Would anybody know what to do ? or do I have to return this router for a refund ?
Thanks !!

 

[ajay11]

I forgot to add that I do not know and cannot see which firmware is factory loaded. And I haven't installed any firmware update through the QIS page (because it feels like fixing a problem I haven't even understood). Such could solve the problem, but it seems like a shot in the dark.

 

[ajay11]

Found the origin of the problem, it was the FF browser (in used and in refreshed config). Apparently the router's UI wasn't happy with whatever FF does. Switched to a very old IE browser for initial set-up, and the problem was gone. Once user and password setup on the router was done, the router's UI was accessible with FF v124,
I am reporting it as sb else may have the same problem in the future.