Doesn't look like there is a solution even though it's now on the compatible device list.
Enjoy reading 32 pages of complaints.
https://community.fitbit.com/t5/Android-App/Samsung-Galaxy-S8-S8-Compatibility/td-p/1946855/page/32
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Best AnswerSuddenly began functioning properly oo effect the weekend. Now receiving all notifications and tracking activity.
At some point, a pop up notified me of something fit bit notification related and allowed it.
Someone at fit bit ought to codify the steps required to get started with the S8/S8+... set up is obviously unclear to many in the community (myself included) it seems like dumb luck that mine started working correctly.
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