The Black bit with the silver bracket you put your chin on has come off of the violin. Also a thin bit of cork has come loose with it? Not sure if I can mend it or it needs to be done professionally, can you kindly please advise.
The Chin Rest is normally held on by rotating the two tube nuts which have a small hole at the midpoint.
The nuts are turned using suitable stiff metal pin (e.g. large paperclip). Open the clamp this way while off the violin, then replace taking care not to scratch the ribs.
The Tube Nuts each have a right and left-hand thread which provides the clamp action.
CAUTION do not unscew completely.
Alan.G
October 2016
Take it in for repair you may mess up the sound box (Body) trying home repair if you don't know what you are doing.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix violins.