Player models showing up as Combine soldier.

Whenever I change my player model, it shows up as a Combine soldier.
However, I can change my model to kleiner and it will be fine.
How can I fix this?

The server I play on alot also had the same problem I think. The owner propably fixed it, I might ask him about it.

Ok, It seems just to be the citizen, non half life 2, and custom player models not showing up.
Heres a list of Models showing up.
Zombie
Breen
Gman
Kleiner
Barney
Alyx
Civil protection