Your unban request may be locked if:
Your unban request has been accepted/denied by an administrator (NOTE: if your ban request has already been denied, instantly remaking one will not increase your chances for unban).
You have lied on your unban request, which may also lead to your ban getting extended.
You posted in the wrong section, unban requests should be posted in the unban requests section under Appeals section.
You didn't use the template.