I noticed that in this event I will get items for feeding, breeding, hatching, collecting, etc at a very fast rate until I reach 1 or 2 items from the required amount and then regardless of how many times I complete the required actions I do not get any new items locking me into one challenge for hours.
This gets frustrating when I am feeding dragons or breeding and hatching.
I have been collecting food at 30 second grow time for an hour trying to get the final 3 items and only received 2.
Is there a cool down period? Any one else experience this?