Hi guys,I've just had my clutch replaced on my fiat scudo 2008 and have recently realised something hasn't been attached again properly and is making a knocking noise when at a stand still on the road,I believe it is the part in the the picture I have enclosed and was wondering if anyone could tell me what it is and how to sort it out?

I would take it back to garage who done clutch, if u start trying to fix it u might cause problems then garage will blame u.