Well, I can't sign free agents. I hit the submit offer button but nothing happens. And the drop down areas, like Role, Salary etc. are always grey. I don't know what to do.

if its in the free agency signing stages - make sure the team is not on CPU control and you make the offer from their playercard 'contract' page.

if its during the season (after the free agency signing stages) you need to sign them from their player profile - where there are "sign to active" and "sign to PS" buttons (on their 'bio' page, if memory serves).

It looks like this:

https://ibb.co/sJzNpvX

An yes, the Team is controlled by me, not CPU.

are you 6 million over cap?

Doesn`t matter who I try to sign. And I have enough free cap.

Are you clicking on advance to get to the free agency screen and opening bidding from there?