05 VW Touran deadlocked driver door?

[Critical_Mass]

Hi all,

Im in the middle of getting a family members Touran into a good condition to pass its MOT before selling it. Problem is the door which was unlocked (dead battery) worked fine until one time i closed it and i may have used the key to lock it. Since then it wont open at all, manually using the key to unlock, even when i fitted a new battery it will not open. You can hear the lock working when using the fob but im unable to open it from inside or out.

Can anything be tried before i rip the door card off? Also seen as the lock appears to be working what could the actual problem be?

Cheers