Lost pets

Exploration Stage: Monster Hotel
From: Detective
Description: Most hotel guests have complained of sleep deprivation. But luckily, I think I'm close to identifying a suspect. I found what looked like a sparkly medal on the floor, but I was in a hurry and couldn't pick it up. Where was it? Can you help me find it?
Completed: This is the tag on your pet's collar. "Contact: Somnia of the Land of Sleep in the Land of Dreams"... this is Somnia, the Queen of Dreams? This means that this tag belongs to her pet. This is definitely the cause of this issue.