I believe the user name and password are both printed on the sticker.
If they don't work then you'll need to do a factory reset so those credentials are re-applied.
Try putting in optus with a lowercase o and not the uppercase O and the password is your wifi password on the magnet - it worked for me after driving me nuts for ages.
Hi, have been able to use the above to get into the modem.
Also does this work for anyone else,
When put in the address bar.
ok ill give that a go thanks.
but cant change the wifi password .
found it why cant optus techs tell you that in the first place.