Stick to Calendar for 7 days. How do we fix it?

Hiya there @ανδριανα please be patient as they will probably bring a fix to this problem soon in an update. Meanwhile, try logging out, clearing your device cache, restarting your device and logging back in to see if you can force it off the calendar.

The alternative is reinstalling the game which has a higher chance of working but i will not recommend due to the loss of boosters.