This bug was fixed in Patch 1.77.146/1.45
My Sim is in a freelancer/decorator/actor and if I click on the button to get a new gig, nothing happens.
The same effect can be seen when clicking to cancel a gig or if an actor tries to invite the director and the co-stars.
Unclear. The buttons just seem to have lost all functionality.
Fortunately it still works to get gigs through the phone. Just click on the option on the phone instead and you should get the gig list (the other options should also appear on the phone)