Product combinations - wrong!

[Cosmi]

Hello,

I have some issues with my shop and one of them that I cannot solve is this:
Lets say I have a product with the following combination:
Color : red
Color : black
Color : green

The problem is every time a user choose one of the values, in cart is added the "red" value (the first value from the list). This doesn't make sense.

Have you ever had the same situation? Where should be the problem?

Thank`s
Cosmi