Cosmicboom

Hello so I was curious. This evening I did the world event and on the last stage with the penguin I completed it. Waited about 10 minutes never got reward logged out logged back in about an hour later and was never rewarded the perks of stage four completion. Do I have to be logged in to receive rewards? And the wait time for reward completion on stage four can take 15-30 min I'm just curious if this is the design so I can better prepare thank you for your time and attention