Cubase 12 Panning

Panning left or right not smooth.
Full left can be heard in left left ear only but full right not only right ear … almost not panned at all

Not enough information.
Did you try this in a new, blank project with a single audio track and no VSTfx?

Will try it … not at studio right now but thanks.

Sounds like you got a mono instrument on a stereo input.