I'm trying to reset the service light on a 2004 320 Ci

I've tried the following but to know avail:
Ignition off
Hold odometer and turn key to position 1
Keep pressed until Oil/ inspection/Reset comes up
Release reset button then press again until Reset begins to flash
When flashing press again. At this stage it should change to 15255 ( however it doesn't)

Does anyone know what I'm doing wrong.

Thanks in advance.