Getting a strange roll after blending cameras

Is there any way to reset root orientation for Gear VR?

With my rail shooter if I make rail that turns 90 degrees to the right, in order for the camera to look straight ahead, player must turn their head 90 degrees to the right. This gives massive neck ache after 10 seconds.

To get around, I add new cameras like this:


It works but then I get this strange roll and it make me very sick.

How do I get rid of roll or is there any way to reset default orientation so I don’t need to switch cameras?

Thank everyone for assistance.