Hi @Doxielover, do you know what version of the app you have on your tablet? Mine has the one from Amazon App Store which is 2.63. This version is from before the release of the charge 3 so I don't know if that would have any effect on it's ability to sync with the newer model. Fitbit always says that the fire tablets are not a compatible device so I doubt you'll get help from them, but someone out there may be able to help. Good luck.
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