Question Author
Found that there is no hole inside to push through which you can open it in emergency like other cars.
Discovered that if someone pressed on the front end of the flap at same time as the internal lever was pulled, the flap would open. What caused the problem is a small piece of plastic has broken off. This piece engages with a "spring" which flips the flap open.
Have fixed myself up with a small piece of wood to hold the lever up, then hop out and push the flap myself.
Thank you all for the advice.
bungy2
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