Vertical axis slanted

I have issues moving object vertically in Rhino - when I choose move > vertical=yes and move an object, it appears slightly moved in the top view as well, depending on the vertical distance. Does it have anything to do with the CPlane? I set it to Top.
Thank you.

Have you by any chance rotated your Top view slightly off axis? If you right click on the viewport title and choose Set view > Top, does that change anything? Otherwise, is it possible that you set a slightly off CPlane in the Perspective view?


Thank you for the reply. I think my top view was off axis, like you suggested. I made use also of the front view to move vertically and now it’s ok.