You can best investigate this yourself. First check your entered age as that can throw off your calculated zones. Zone minutes are based on your heart rate. Tap the Zone Minutes to see the heart rates needed to reach Moderate and Vigorous zones, some places called fat-burn and aerobic zones. If you are normally aware of your heart rate at all, do these numbers seem ridiculously easy to achieve? Then look within the zone minutes part to see where it says you are getting them to see if you were active then; and look at you heart rate chart to see if it looks reasonable, or does it seem to often be much higher than you would expect.
Before posting, re-read to see if it would make sense to someone else not looking at your Fitbit or phone.
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