If a participant reaches out to you and says they have completed specific parts in a course, but it looks like they haven’t, you can easily double-check this by following the steps below.
Go to the "Participants" tab
You will find a progress percentage bar to the right of the participants’ names. If you click on the plus sign to the left of their names, you will find more details about the participant's progress, such as which modules and activities they completed and when this was completed. If you click on "Show details" you will even see which components in a specific activity they have completed.