I've had this problem too. Here is my workaround:
- Close the app
- Put your device in airplane mode
- Open the app settings and clear the cache
- Open the game and go into an adventure level
- Turn airplane mode off
- Play the adventure level
After playing, you should see the popup in the bottom right about a quest being completed and be able to claim the daily reward.
For what it's worth, I've only had this problem when I don't have a "plant of the week" level / quest to play. So I only do one plant of the week level a day and then do this workaround for the last day or two of the week.
I still wish they'd fix this bug since it's been going on for a long time!!
