I have seen some topics related to this problem but I think mine maybe slightly different.

The door wont unlock dispite the other 3  working OK

If I pull the internal handle the locking bolt on top of the door trim pops up but the door won't open

Ant help would be appreciated as I often ferry elderly people around and at the moment none of them can get in the front!

Haaaa! I have EXACTLY the same problem. Can NOT figure out what causes the issue. Can't even open the door to remove the door card to find out lol

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My door that won't open is the rear passenger side.

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And MOT time in December. FAIL!!!

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Got to smash the lock in and twist the gears then replace locks, should be similar to the guide in Fabia Tech Guides section

Before you go smashing stuff up remove the rubber condom thing and check the wiring that runs threw it. You can do that on the rear door easily by opening the front door.

Might struggle on the front door tho :(

Thread braught back to life, was this sorted as im in same boat with front pass door being deadlocked