Mk2 Fabia Estate Rear Door

Fabia MK2 estate 1.9TDI rear door central locking is locked on dead lock looks as though  the motor has gone, it's not having it trying to open it tried banging door with palm while trying to lock -unlock so looks like i'll have to try and remove card panel off with door shut and locked

Has anyone had this issue and if so can give me some pointers to remove card and get the door unlocked so I can replace the lock/motor

Thanks in advance