A participant I am tracking appears to have stopped. Why is this?

We recommend participants set up GPS tracking to allow friends and family to monitor their progress as accurately as possible. If a participant has stopped, then they won’t move on the map. If a participant has lost GPS signal or run out of battery their phone will no longer send a GPS signal, which means that they will stop moving on the App map. However, the timing chip in their bib number will still send updates to the App so they will continue to progress along the route.