Roller cam and lock mechanism dropped on window

A few of our double glazed windows are struggling to open or close.

The problem being is the bottom roller cam seems to have worked loose from the handle and drops. So when the window is open it drops and the metal lock mechanism hit the window frame and the window will not close. If i press it up with my hand to close the window it will drop whilst closed and therefore very hard to get the window open again

Is the lock mechanism broke?

First image you can see the lock mechanism has dropped.

looks like the shootbolt has dropped from its serrated edge within the lock. If you take the lock out , you will probably find a gearbox that connects to the cams/bolts via a 'serrated' edge, you can normally push these back into the correct place, normally happens if the handle has been forced....could be the gearbox at fault to though

Thanks. Will give it a go. Need to get my ladders out for a proper look as its in the bathroom.

Most likely going to need a new gearbox as Ronnie says.
Life will be easier if you remove the screws holding the hinges to the frame and bring the whole sash inside to investigate (you may want someone to hold the sash while you do this).
When you have the gearbox out take lots of photos, write down any code/numbers and take lots of measurements.
With a bit of luck googling the numbers will give lots of results if not send pics and sizes to these guys http://www.northwesthardware.co.uk/