Camera Focus doens't work while first person?

Hello, So, I tried everything, but CurrentCamera.Focus doesn't work at all while you're in first person? Just try and zoom in to First Person, and run the script, what's the result? nothing. Here is an example:

game.Workspace.CurrentCamera.CameraType = Enum.CameraType.Scriptable -- You could use Fixed, but you might still want to move the camera.
game:GetService("RunService").RenderStepped:connect(function()
    game.Workspace.CurrentCamera.CoordinateFrame = CFrame.new(10,50,30) -- You can use a variable if, for example, you want to zoom in or out.
3
    game.Workspace.CurrentCamera.Focus = CFrame.new(0,10,0)
end)

If you have any Idea on how to fix Camera Focus in First person mode, I appreciate your help.