External Back Door – Alignment Issue / Possible Hinge Replacement

I am looking for an experienced door/window repair specialist to inspect and repair my external back door. There is a visible gap along the top of the door where it meets the frame. The door does not appear to be sitting correctly within the frame, and I suspect it may have dropped or become misaligned. A plumber previously suggested that the hinges might need replacing if the issue persists. Work required: Inspect the door and identify the cause of the gap. Check whether the door has dropped or become misaligned. Inspect all hinges for wear, damage or loose fixings. Adjust and realign the door so that it sits evenly within the frame. Check the rubber seals and ensure there are no gaps allowing draughts or water ingress. If necessary, replace faulty or worn hinges. Ensure the door closes properly, seals correctly and locks securely. I have photographs showing the issue and can share them before the visit. Please provide an estimate covering labour and any replacement parts separately. Ideally, I would prefer to repair and realign the existing door rather than replace it. Please confirm your availability with uPVC/external glazed door repairs.