Hi there,
Mine went like this, a mate slam-locked it (you know holding the button in when you lock it then shutting the door.
The rod from the lock button to the loxk over-centred, so I had to take th einner door pannel off with the door shut.
It's tricky but can be done, taking the seat base out helps then remove window winder, handle, and the other trim bits then I managed to lever the top open enough to get my hand down and un-over centre it, then it opened just fine!!!
Just keep at it and good luck!!!
Jason.