Nokia Go Manual page 6

The Nokia Health Mate® app keeps your entire history, allowing you to easily track
how your sleep data evolves over time.
Changing the way I wear my Nokia Go in the app
It is required to specify how you wear your Nokia Go in the app. The reason for that is that sleep
and swim detection are only enabled when the app knows you're wearing
your Nokia Go at the wrist. To update this, perform the following steps:
1. Open the Nokia Health Mate® app.
2. Tap My devices.
3. Tap Nokia Go.