Hi ,anyone to advise me as my corsa wont unlock ,when trying to unlock using the remote it unlocks then locks quickly.I have to unlock using the key. All the buttons are working ,moving up and down.

sounds like one of the door switches is faulty and the system believes one of the doors is open.
Try opening each door in turn and see if the interior light comes on and goes out after a short period
When you find one that neither switches the light on or off then there is the problem

Don't forget also the tailgate as this will also affect the central locking