Please always choose None at Spine atlas textures to save you a lot of troubles (also see Runtime Packing - Important Note box on the documentation page). To nearest and To smaller will potentially mess up your image, as the name says resizing it to a smaller image size that is a power-of-two.

In general we would however recommend to always export your atlas textures as power-of-two in the first place, unless you have a clear reason not to.

You're welcome. 8)