The release is shown in the parts book but I can find no mention in the owners manual. Anyone know if it’s existence?
ok update! It is found in right side of inner trunk behind the right side trunk carpet. Remove two plastic fir tree plugs, pull back the carpet and it is a red button pull at the snout of the gas tank filler shroud.

 

 

The original post was because my gas flap was stuck. What I found was the latch for the door had dropped into the body pulling the gas flap door into the body below the cars outer skin. The result was removing the right rear wheel well liner to access this latch. Very weak link for such simple action of closing a filler cap. Awaiting new parts and wondering how often this might happen.