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Sorry @Julifit, not all the features are available on the Galaxy S8 right now - some do work as you discovered, keep watching this list, once it is added all fitbit features will be compatible. Engineers are working as quickly as possible.
In the meantime you might check the Having trouble syncing? post and follow the instructions provided there - my fingers crossed everything starts communicating for you 🙂
Appreciate your patience, welcome to forums!
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It's great to welcome you @joseph1stre, @Julifit and @wmchapman thanks for stopping by.
Samsung Galaxy S8 and S8+ are already in our list of compatible mobile devices, but since they were recently added, there are some issues connecting the trackers with them but you can always try and follow the instructions provided in the My Tracker isn't receiving notifications (Android App) post by our friend @MarreFitbit.
Let me know the outcome. 
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Community Moderator Alumni are previous members of the Moderation Team, which ensures conversations are friendly, factual, and on-topic. Moderators are here to answer questions, escalate bugs, and make sure your voice is heard by the larger Fitbit team. Learn more
I am glad to hear that you are receiving your notifications @joseph1stre and that your tracker is now working. If you need anything else, do not hesitate in posting it.
Keep the stepping up! 
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