Lua Arena room

[God Sallonzo]

Hi

When i walk on the teleport at the arena quest in svargrond i get this in my server window

[21/02/2015 15:14:46] [Error - MoveEvents Interface]
[21/02/2015 15:14:46] data/movements/scripts/arenaroom.luanStepIn
[21/02/2015 15:14:46] Description:
[21/02/2015 15:14:46] (luaGetCreatureName) Creature not found

[21/02/2015 15:14:46] [Error - MoveEvents Interface]
[21/02/2015 15:14:46] data/movements/scripts/arenaroom.luanStepIn
[21/02/2015 15:14:46] Description:
[21/02/2015 15:14:46] data/movements/scripts/arenaroom.lua:31: attempt to concatenate a boolean value
[21/02/2015 15:14:46] stack traceback:
[21/02/2015 15:14:46] data/movements/scripts/arenaroom.lua:31: in function <data/movements/scripts/arenaroom.lua:1>

How do i fix this ?

Thanks