Adjusting my upvc front door?

Hi All, i am hoping someone may be able to help me with a problem that i have, my upvc front is the problem, at the moment it is not actually level when i have checked and there seems to be a gap at the top left corner as i am looking at it from outside to were it closes, i have noticed that there are 3 hinges on the frame to which two has (bolt pins) if you call them this to which go through each hinge with a top and bottom allen key grub screw,
Now i have said all that is there any way of me adjusting the door to raise up roughly 5mm at the top point of the door and if so can anybody please explain how to do this, Thankyou for your time

Many Thanks