Fitbit Alta HR Notifications w Note 9 - not working

[French]

So my Fitbit Alta HR would vibrate and display a message for when I received text messages and calendar appointments on my Note 8. It no longer does it with the Note 9.

Anyone else experiencing this? The primary difference (which wouldn't surprise me if it's the actual issue) is that I had an unlocked Note 8, but the Note 9 is VZW branded.