It sounds like your door has droped and neads toe and healing,this will be the only way to rectify this problem correctly as it will get worse when warm weather comes and your door swells with heat,but for a quick fix by adjusting hinges that are 3d adjustable hinges by popping the cover caps off,they are underneath the part that goes on door frame and on the side of the part thats on sash,then adjust with an allen key,you have to adjust all of them the same.Good luck and hope this helps
shaun www.sdwupvcrepair.co.uk, February 2008
