1999 Other Nissan Models central door locking

hi there i have a 1999 nissan micra when opening the central door locking all doors lock straight away again and you have to keep opening it 4 or 5 times once in the car you press open on key blip again it locks itself and the only way to keep car open is to hold the lock on inside of n/s/f door if you hold any others the car still locks HELP!!!!!!!