Have you finished the event? Once you finish with Olivia and Meredith go to the upper right corner of the garden where Meredith was. Also try to find the purple firework and purple berry or something like that.
In the grid when you walk out of the house. There are people standing in front of it. One of them is for Meredith queen event, one of them is for Halloween event and the last one is for the new special event.
