According to replies on a post entitled 'Note 8 Freezing and unresponsive' in Samsung's forums, many variants of the Note8 are having this problem. Most of these reports are occurring when the user is doing something concerning calling and texting, leading us to believe that it's the contacts app that is the culprit. Here's a list of what is causing Note8s to freeze that we've gathered from the forum post and its replies:
Using speed dial
Making calls from the recent calls list and contacts
Tapping on contacts in the Phone app
Tapping on contacts in the Messages app
Loading an Excel spreadsheet from an email
Opening contacts
Using the contacts list
Using Pokémon GO, Chrome, and the Google app
Tapping a contact in the Messages and Contacts apps
Charging overnight
Opening the Phone app
Opening an individual contact in the Contacts app
Opening Contacts while texting
While making a phone call