BMW320, door locks stay locked off remote and only driver door opens inside?

I have a BMW 320 estate, 2003 plate. The door locks started to not respond to the remote key about a week agobut not all of the time and today stopped responding completely. I can open the drivers door from the outside lock with the key but the other doors (front and back) stay locked. When locked, only the drivers door opens from the inside lever.
Hope you can help.