Occupant chair knocking

Hi Have a Giuia Veloce 2021 with 25 km A while ago when I used to speed over 170-180 the chair keeps shaking but with no visible sound At that time thought it’s the head rest or so but didn’t bother I went to the agent for oil change And I travelled with the car today’s After couple of hours the chair started to sound like whisking or as if there was something loose moving around Stoped several times tried to check and play with the automated mechanism Then found out when you lift the chair up sound slows down but stil you can hear knocking or shaking on high speeds Anyone with same issue This chair never been used by anyone