Sims aren’t able to “move on”

I am on level 51, almost 52…and out of nowhere this happened. The majority of my Sims are old, as I’ve been grinding to get life orbs. However, now I can’t make any of them pass on; it’s saying: “[Sim] is required for the tutorial. Complete more tasks before removing this Sim.” I don’t have a tutorial though? I’ve had the road task for over a year at this point, so I don’t think it would be an issue—I just keep putting it off (and I only play 3-7 weeks a year haha)—right? If someone could explain what this is and/or how to fix it. I would delete the Sims and hope that the new Sims would age and die fine (if that even happens because I don’t have a tutorial), but I would hate to waste over 20 life orbs.