I'm currently playing the acting career in the current generation I'm in and I have the same bug. I know some people have said that if you complete them at home and go to the studio they show as not started but they would still be completed despite that. This isn't the case at least for me. My sim will mess up the actions so what I ended up doing was completing as many of them at work and then doing the safe options for the ones that I didn't have time to complete at work.