can't scale only at Z I cant scale the Z
but at X and Y it still works fine
it made from extruding cylinder and try to scale down the Z from 3 edge
sorry for bad english, im also new
You can't scale Z when the selection is already scaled to Z = 0 (they are equal position and you are using Median point pivot). You'll have to manually create a different in Z between them to be able to scale, otherwise use a different pivot point.