On the main dashboard, scroll down and tap Period (under the General header near the bottom of the page).
Tap the day you'd like to edit.
Use the toggle beside Are you on your period? to indicate that you were on your period during the day you’re editing.
Tap Save.
You can enable or disable the ability to track your period by tapping More > Data Visibility > Period Visibility, and then toggling Period Tracking on or off.
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