1999 Boxster Door Lock Issues

[project986miami]

HI.

I have a 1999 Boxster. I can lock both doors manually with the key on the passenger side but on the driver side the key moves right and left without the click you hear on the passenger side when locking.

What is broken on my driver side lock. It was working then just stopped locking? But again it locks from the passenger side

Thanks for any help