I can't open a bedroom double glazed window even though the handle is in the open 9 o'clock position. When I move the handle it feels quite loose and can hear the mechanism working but it won't go all the way down to the shut position. I've tried WD40 and a different handle but neither made any difference. I've also looked at another window open and can see the top of the mechanism goes up into the two slots and the bottom goes the opposite way but I would have no idea how to free to actually get the window to open.
Any help would be much appreciated