Players aren't banned just from what people think. Even mass reports only lead to an investigation.
Anyways, if you wish for an account to be unbanned, a ticket must be logged.
To log a ticket click the support button at the top of this page.

You may be asked to log in depending on when you last logged on to the Nexon website.
On the next page, you should see a Log a Ticket button.

Click this and then fill in your ticket.