When you begin the game, Rowan, the harvest sprite, will immediately tell you the reason why they are in dire need of help. Somehow, the people of Chestnut Town has lost some of their precious memories when the mystical Harvest Tree lost life ever since the farm was no longer maintained.
To bring back the lost memories, you will have to just keep on working on the farm to bring back life in the farm. Aside from that, you will have to help the people bring back their memories by talking to different people and getting to know them more (their likes, dislikes, birthdays, etc.) a little each day.
Once you’ve triggered a memory, the name of the memory will show up on the screen. Each memory will have a reward waiting for you so be sure that you will have enough space in your Rucksack or your Storage house so you can claim the reward.