I want platforms to only move in y

I have platforms moving down, but I would only like them to move in the y direction, not the x and and y direction. Does anyone know how to fix this?,I have platforms moving down, but I would only like them to move in the y direction, not the x and y direction. Does anyone know what to do?

is your project in 2D or 3D?

does the object need to be pushed to be moved or is it just a automaticaly moving platform?