How to change forgotten password?

[Kokurokoki]

So I made a PSO account for my sister a long time ago, and she wants to play together with me now but can't remember her password. Can anyone point me to a guide or help me reset her account's password?

[Anduril]

https://cha.isao.net/profile_oem/OEMPassResetStart.php?product_name=sega&return_url=/profile_oem/OEMLogin.php?product_name=sega
You need to know all the information you signed up with, such a secret question.