How to replace a smeg to oven door?

I can't get my smeg top oven door back on. It is the type where you used an allen key to hold the hinge.
I have watched a similar video on you tube but the hinges on that one seem shorter. Mine has a long hinge with a hooky bit on the end. The main problem, I see, is that I can't seem to get the groove on the lower part of the hinge to sit on the main part of the oven, which allows me to then tilt the door back up to the position I took it off it. Not sure I'm explaining well. Have looked at smeg instructions, not helpful. Any advice gratefully received.
K