Help!! Locked out of mk4 gti after changing battery

[silver16v]

Hi, would really appreciate your help getting back into my mk4 golf.

I changed the battery yesterday, and the car started up fine, and locked with the keyfob remote normally.
Tried to get in this morning and keyfob won't unlock car, if I try to open manually using the key it just seems to turn in the lock without opening.

Any advice gratefully received!!

Cheers, B