This page explains how to solve the quest "Y-Cola to the Rescue!" in Yo-kai Watch.

Buy a Y-Cola!

Near your house in Uptown Springdale, the mother of a little girl gives you $1.20 and asks if you could get a Y-Cola and bring it to them. There is a red vending machine nearby where you can get it. Give the Y-Cola to the mother after you get it.