Failed change game name!

When i bought a change call name i tried to change it and put in my new names.
Look, at this:
Change in game name << Back to the item list
Old Call Name iHallowed
New Call Name loltboy
New Confirm Call Name loltboy

Please input correct old name.

What does this mean?
I can't even change my old name as it is predefined and it is correct.
Now, my ZP is lost and i have no change name left!!!
This is really an outrage.
I want to change my name and i am unable to due to an error!