I don't think this is the fix this time... something else is wrong. Normally this works what you are saying to do, even though I don't believe we should ever have to do this, but due to poor programming EA always leaves it up to their uses to debug their programming.
Something else is wrong this time... I was playing just find. Decided I would check out the event, I had almost by accident been outside.. so I got some rewards, I claimed the first two items. Then I played a bit more and thought I would check out the event. I clicked on the event in the upper left hand corner... the second I clicked on the event the game crashed!
I am playing on a new powerful MAC with 32G Ram... so I know the issue isn't my computer not have the power or the memory.
I have played so many games in my life... never have I had the consistency of problems involving updates that I have with Sims.... most games you see there is an update or DLC, you get very excited, with EA on the other hand... you know you are going to spend hours trying to not loose your saved game play and try to get the thing to work again. I just find it odd that for some reason we are supposed to be okay with this because it is so often like this with updates.