SKODA Fabia 1.2 TSI SE. Unable to open front passenger door from inside.

Hi, Just upgraded from my Mk1 Fabia aka Leaky Linda. After thinking my troubles were over with the water leaks, i tried to open the passenger door - its been fine all the time but today I couldnt open it. Before I go ripping off door linings is there any setting that could cause this?

I opened it from the outside and it was fine, then lifted and closed the outside leaver a few times and the inside started to work !

Thanks for any advice. Andy.

PS; Where do I bet my first water leak will be, as I passed on the fish from the other car to the new owner.