You need to do force close it a couple of times, until you don't have any finished events pop up again.
I do not work for EA
Yes. This happens to me too. And it is happening with the winter quest. I was in the cafe event with 6 hours to go. Closed the app for about an hour, came back and it said my sim had just completed a long hangout (which they haven’t been set to do in weeks). My other 2 sims had been working long shifts, but when I logged back in, it said they had just finished quick shifts. The worst part is that now when I click on a couch, I cannot even see the choice of completing the Cafe quest event, and that is the next event I need to complete. I am very upset that these problems (which have been happening to me since the harvest quest) are going to cause my winter quests to be ruined.
Thanks everyone for your feedback and reports, sorry to read this is still happening for you. The team is still working on this issue, but in the meantime, I would like to share again the workaround that can help with this:
1. If any Sims have completed events that are ready to be collected, collect those.
2. Close your game completely, also in the background.
3. Open The Sims Mobile and collect events again.
4. Please, repeat these steps until events are no longer appearing as complete neither changing. Depending on how many events your Sims are stuck in, you might need to do this more than once.
Please, give it a try if you haven't already, and let us know how it goes.
Thank you for this. I just followed your steps and had to open and clear tasks in the app three times before I opened it to find all events done. The extra strange thing is that it was telling me that relationship tasks were being completed but it was showing my sim at work. Hopefully this fixes the issues going forward and there won’t be any during winterfest. Thanks again!