Sometimes clicking Play does not start at PlayerStart

I just finished this tutorial in a new project: https://docs.unrealengine.com/latest/INT/Platforms/SteamVR/QuickStart/2/

I added a “PlayerStart2” into the world set at Location 0, 0, 0. When I click Play, my VR headset isn’t set relative to 0, 0, 0. The headset perspective is too tall.
I then move it o 0, 0, -56, but my VR headset perspective doesn’t change. It’s at the exact height as before.
Finally, I move it to 0, 0, -1000 and then my headset is now positioned relative to -1000 on the Z axis.

Why?

I also tried following the tutorial’s suggestion of

If it feels like you are too close or
too far away from the virtual floor,
open the VR_Pawn Blueprint, select the
Scene Component that the Camera is
parented to and adjust the Z height
value up or down till the floor feels
like it is in the correct location for
your height.

I changed the Z height many, many times but it seems to not have any effect on the VR height perspective.

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