Attribute url #/ not working

[Psycox]

Hello, attributes works ok when you add them to cart. But when I enter in a product page, the url stays with the default attribute and it doesn´t change when selecting another attribute.

 

So lets say my default attribute is size 10, so when I enter to the product I get ...gold.html#/3-size-10.

And if I select size 12, the url stays as ...gold.html#/3-size-10. It doesn't change.

 

I've tried to search a solution but I didn't find anything.

 

Thank you.