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It's nice to see you around the Community @s4wyt 
! Hmmm...very strange let me say. Have you changed something on your settings or so?
As you may have read in our article on the topic What are active minutes?, our algorithms detect subtle differences in exertion that may explain why two seemingly identical activities result in different active minute totals. For example if you took a brisk walk along the same route two days in a row, differences in your speed and exertion levels (e.g. out of breath vs not out of breath, etc) will cause different active minute totals for the two activities. Also keep in mind that active minutes are only recorded for activities that last 10 minutes or longer.
Because our trackers primarily track movement through the use of an accelerometer, they more accurately detect active minutes for step-based activities (brisk walking, running) than non-step based activities or activities that require more than steps (yoga, tennis). Trackers with a heart rate monitor detect active minutes most accurately, since heart rate data allows us to better estimate caloric burn and, in turn, exercise intensity. If you're unhappy with your active minutes total, we recommend logging the activity manually as described in the previous topic. Manually logged activities override your tracker's data. Sometimes customers report a decrease in active minutes after logging an activity, which can occur if what your tracker recorded was more intense than what you logged.
If you still have reason to believe your tracker is recording active minutes inaccurately, please contact Fitbit Support diectly with the date and time of the activity(s) in question so they can investigate your account and troubleshoot the issue.
Have a great weekend!
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