im new here and need helps to add my 3d model

im new here and still play around with the engine

i got my 3d model made in MAYA and i exported it already as .DAE file

when i added this up on to my level , i got it works ,it does appear

but....

this model is like "untouchable" and the player can walk trough it like nothings there.


anyone ,pls help me ..:(

cheers

(sorry for my bad english , im still learning)