OVRPlayerController left stick doesn't move player around environment

Hi, I have a test scene with an OVRPlayerController where I can rotate with the stick on the right controller and walk forwards and backwards with the stick on the left controller which works perfectly.  Then I created an OVRPlayerController in a scene that I have copied from another project.  The player seems to work fine, I can look around with the headset and rotate with the stick on the right controller.  But the left stick doesn't move the player around.  What is the best way to debug this?