Clio 1.5 Dci 2003 - key resync using central lock button

Hi



I have just dug out my spare key and it's not doing anything - won't unlock the central locking or even start the car manually.



I've replaced the battery and still nothing. I've read on here the steps to resync - turn ignition off, press central locking button for 5 seconds, etc, etc.



However my problem is that holding the central locking button down doesn't do anything, other than lock the car. I'm using the button in tyhe centre near the radio - is that correct?



Thanks.