How can I change the value set of the rating model when I add a competency to a model profile?

Summary

How can I change the value set of the rating model when I add a competency to a model profile?

Content

Hi everybody,

I need to add competencies to a model profile (job/position profile) but when I try to add them I cannot choose the correct level of rating model. I linked all my competencies to Performance rating model but during the creation of the model profile it only shows the Proficiency rating model (from which I cannot choose anything in the list). I went to content section area and I see that I don't have the possibility to change the rating model I want to use (as you can see in the attached picture). How can I change it inserting the Performance