Hi @Noodle12009 as you will have probably seen the messages at the start of this forum by now, your tracker is fine. Fitbit have just done their usual thing of sending out an android update that doesn't work properly. So we will all have to twiddle our thumbs until they issue another update.
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I've seen in some of those messages that following an update a restart of the phone and fitbit can kick things back into life. See https://help.fitbit.com/articles/en_US/Help_article/1186/ for instructions to restart the fitbit