I just finished a chat with an agent who informed me the reason I have been unable to receive notifications on my Inspire HR is a "current known issue for customers who have iOS 12 version of device." (copied directly from the chat). When I asked about other models, ie, the Charge 3 Special Edition, I was told "The issue is not with Fitbit trackers but the connection between these and iOS 12 devices."
I made the choice to switch back to Fitbit after using a cheap $35 fitness tracker that was wonderful in all respects except tracking sleep. I did not have a bit of trouble with notifications. Who says Fitbit works better than cheap trackers?! Not in my experience!
Best Answer
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This problem has been affecting some people since September last year. The main thread for it is at:
https://community.fitbit.com/t5/iOS-App/No-notifications-after-iOS-12-update/m-p/2980360#M94829
There you'll see comments from fitbit and some suggestions for things to try. Sadly, though, no solution as yet.