Pokémon Sleep requires permission to access Health (iOS) or Health Connect (Android).
For iOS devices, go to Health > Browse > Sleep > Data Sources & Access, and make sure Pokémon Sleep is enabled under ""APPS AND SERVICES ALLOWED TO READ DATA.""
For Android devices, open ""Health Connect"" on your device, select 'Pokémon Sleep' from ""App Permissions,"" and turn ""Allow All"" to ON.
Please see the official Pokémon Sleep website for more details:
https://www.pokemonsleep.net/devices/
For Android devices, you must allow your data source app (such as the Fitbit app or Samsung Health app) to access Health Connect.
Please refer to the official Fitbit or Samsung websites for more information.
• Fitbit:
https://support.google.com/fitbit/answer/14506680?hl=en
• Samsung Health:
https://www.samsung.com/us/apps/samsung-health/#Sleep