I would recommend restarting your Ionic by pressing and holding the left button and bottom right button together for 15 secs. Hopefully this will solve your issue.
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@SunsetRunnerLooking at your image it shows what must be periods of inactivity.. at a speed of of 1/2 mph for about 500 yards... and I presume your GPS was trying to connect all of the time.. As @N8teGee suggests, do the restart.
The Fitbit should have picked up those steps even without the GPS.. Pointing towards hardware..