If your team is closing all their stories and tasks on the last of the sprint you should consider moving your sprint duration to being one day.
This sounds dumb right?
So is holding onto work that has no movement on it for two or three weeks and then magically closing everything on the last day.
If your not sure if your team is guilty of this practice, check the work completed on the last day of the Sprint is it 85 hours across 5 people?
If so, you might want to check where the issues lie in updating their work throughout the sprint as opposed to doing it on the last day.
It might be a simple case that they don’t know what they are doing (and that is a good problem to have and to solve).