Why can’t I unlock 53?

To unlock scenes and progress in the story, you need to add more Flowers to your island. How many more Flower you need is indicated next to pink flower icon on your main page. Flowers can be obtained a number of ways, including taking items out of storage and buying new decoration. If you buy, you must wait for the construction to be complete and remove the red ribbon, before it's Flower value will count. Buying higher Flower-value decoration will advance your game further. Buying too many low Flower-value decoration and you'll run out of space. Other ways to add Flowers include upgrading buildings, renovating landmarks, sending Jack on missions with Flower/decoration rewards, and winning rewards from time-limited events.