This has been a problem for at least 3 years now. You are clearly adding activities to a person's challenge total on upload and then never adjusting those totals if that activity is updated. 3 years ago this happened in a running challenge where my friend's bike ride was initially uploaded as a run. He edited the activity to be a bike ride, but the activity continued to be included in his challenge total. Currently in a challenge another friend created a manual 50 mile run entry and then deleted it. It is still counting towards his challenge total.