Good afternoon and thank you very much for your question.
Your vehicle is fitted with a dual mass flywheel (DMF).
A Dual Mass Flywheel is basically two components (the primary & secondary mass) linked together by a damping mechanism within the secondary mass and located by the central carrier bearing. The damping mechanism is there to absorb the torque loads of the crankshaft and to help deliver a smooth transfer to the road wheels via the clutch.
As time passes and the vehicle's mileage increases the damping mechanism softens and weakens. As the mileage increases the damping mechanism becomes weaker to the point where the movement between the primary and secondary masses becomes excessive. When this happens the flywheel tends to vibrate or rattle when driving, and sometimes when starting and switching off the engine.
I suspect that this is what has happened to your car. The bad news is that the DMF and the clutch assembly, including the bearing, will need to be replaced.
It's difficult to predict how long you will be able to continue to drive, but I would suggest having it looked at sooner rather that later, as they can fail suddenly.
I hope this answers your question.