Account email

• Is confirming my email address really necessary?
• Can I change my account email address?

ID/Password

• I forgot my ID. Is there a way for me to log in?
• I can't log in because I forgot my password.
• I managed to log in, but I want to change my password.

Level

• How does the level system work, and what should I do to be authorized?

Settings

• I want to change my system language.
• Can I adjust my notification settings?