Fuel flap not opening with central locking

Hi

Have a 2006 A3, 2.0L. Fuel flap wasn't working when I bought the car a year ago but then started working. Now it's decided not to work, only it's locked! Looked at manual release methods but all seem to be for later models where there's a door in the boot interior panel with a cord to release it. Nothing visible in mine so do I need to remove the entire panel or is there another way? I'm assuming the solenoid has died so when I get it open I'll try to keep it open unless a new one is cheap enough.

Thanks for any help.