Making A Simple Elevator Using CFrame and not working?

I am trying to make a simple elevator using CFrame, as I am just starting out with LUA. I am trying to make it so when you chat a message the script will execute, but it is just not working. I know it is a long script, but I haven't figured out how to shorten it.

p.Chatted:connect(function(msg) 
if msg=="://Down" then 
game.Workspace.Part1.CFrame	=	CFrame.new(0, 56, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 55, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 50, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 45, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 40, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 35, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 30, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 25, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 20, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 15, 0.5)
wait (.1) 
game.Workspace.Part1.CFrame	=	CFrame.new(0, 10, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 5, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 0, 0.5)
wait (.1)
elseif msg=="://Up" then 
game.Workspace.Part1.CFrame	=	CFrame.new(0, 0, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 5, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 10, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 15, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 20, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 25, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 30, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 35, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 40, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 45, 0.5)
wait (.1) 
game.Workspace.Part1.CFrame	=	CFrame.new(0, 50, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 55, 0.5)
wait (.1)
game.Workspace.Part1.CFrame	=	CFrame.new(0, 56, 0.5)
wait (.1)
(end 
end) 

Well, first let's shorten this. You can do this using for loops. These are loops that will only run a specific amount of times. You can see them in action below.

p.Chatted:connect(function(msg) 
	if msg == "://Down" then 
		for i = 1, 11 do -- Adjust the '11' to however many times you want the for loop to run.
			game.Workspace.Part1.CFrame = game.Workspace.Part1.CFrame * CFrame.new(0, -5, 0)
			wait(0.1)
		end
	elseif msg=="://Up" then 
		for i = 1, 11 do -- Adjust the '11' to however many times you want the for loop to run.
			game.Workspace.Part1.CFrame = game.Workspace.Part1.CFrame * CFrame.new(0, 5, 0)
			wait(0.1)
		end
	end
end) 

Note the line game.Workspace.Part1.CFrame = game.Workspace.Part1.CFrame * CFrame.new(0, -5, 0). That code will take the existing CFrame and add to it. Here, we're adding -5, so it goes down.

Also, have you defined p? If not, an easy way to do that would be to add this to the start:

local p = game.Players.LocalPlayer

Note that this requires your code to be in a LocalScript. You should put the local script somewhere like StarterPlayerScripts, which is inside StarterPlayer.