It's possible that your TrackR simply needs to go through a battery reset. To reset the connection, turn off Bluetooth on your phone then remove the battery for a minute then reinsert. You can see how to remove the battery with the following video:
Press the button on the face of your TrackR after reinserting the battery. It should light up and beep. If it does not light up and beeps, turn Bluetooth back on and open the TrackR app. Your TrackR should now be connected. If it does not light up and beep, or reconnect to your phone, then you may have a dead battery.
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