I'm looking to make a bunker door that goes up, then down. Yes I have made the measurements, but when I tested it, it didn't even move when I clicked the button? Here's a sample:

while game.Workspace.NAAFBunker.Door.Position.y ~= 20.1 do
	game.Workspace.NAAFBunker.Door.Position.y = game.Workspace.NAAFBunker.Door.Position.y + 0.1
	wait(0.1)
end
wait(5)
while game.Workspace.NAAFBunker.Door.Position.y ~= 11.1 do
	game.Workspace.NAAFBunker.Door.Position.y = game.Workspace.NAAFBunker.Door.Position.y - 0.1
	wait(0.1)
end

You need to use CFrame, not Position, when moving the door.

ROBLOX is stupid, and if you use Position, it won't allow intersections between two difference parts.

#Edit

As other people have pointed out, you also apparently can't set on a single axis.

#End edit

door = Workspace.NAAFBunker.Door

-- Don't use ~= and == when working with decimals
while door.Position.y < 20.1 do
    door.CFrame = door.CFrame * CFrame.new(0, 0.1, 0)
    wait(0.1)
end

wait(5)

while door.Position.y > 11.0 do
    door.CFrame = door.CFrame * CFrame.new(0, 0.1, 0)
    wait(0.1)
end

However, you can also use the strangely named "lerp" method for slightly nicer, more efficient code.

door = Workspace.NAAFBunker.Door
height = door.Size.y
closedCFrame = door.CFrame
openCFrame = closedCFrame * CFrame.new(0, height, 0)

for i = 0, 1, 0.05 do
    door.CFrame = closedCFrame:lerp(openCFrame, i)
    wait(0.1)
end

wait(5)

for i = 0, 1, 0.05 do
    door.CFrame = openCFrame:lerp(closedCFrame, i)
    wait(0.1)
end

or something along those lines

NB

The reason we don't use == and ~= when working with decimals is because computers don't actually store them properly. What looks like a 2.1 is probably actually a 2.1000000003 or something.

The operators == and ~= check for exact equality, so if we're checking for 2.1 and the real value is 2.100000003, they won't work as we expect.

When attempting to move a part, you must use Vector3 or CFrame. You cannot operate on a position regularly

x = game.Workspace.NAAFBunker.Door.Position.X
y = game.Workspace.NAAFBunker.Door.Position.Y
z = game.Workspace.NAAFBunker.Door.Position.Z

while y <= 20.1 do
game.Workspace.NAAFBunker.Door.Position = Vector3.new(x,y+0.1,z)
wait(0.1)
end

wait(5)

while y >= 11.1 do
game.Workspace.NAAFBunker.Door.Position = Vector3.new(x,y-0.1,z)
    wait(0.1)
end