Objects won't follow mouse in a placement system

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#1

My objects won’t follow the mouse when I make a placement system. Before, when experimenting with one object, it worked fine, now it seems that the objects just get cloned and stay in the same position. I used a text box, so the user can type in the object’s name. I have already checked the names, as well as printed out statements, and everything is correct.

There is an error:
Players.Awesomemode14.PlayerGui.PlacementScript:34: attempt to call a nil value

Here is part of of my code:

textbox.FocusLost:Connect(function(enterPressed)
	if (enterPressed) then
		if (objectFolder:FindFirstChild(textbox.Text)) then
			local obj = objectFolder:FindFirstChild(textbox.Text)
			local newObj = obj:Clone()
			newObj.Parent = game.Workspace
			part = newObj
			startPlace = true
		end
	end
end)

while true do
	wait()
	if startPlace == true then
		CalculatePosition(part) --here is the error (line 34)
	end
end

function CalculatePosition(model)
	CheckCollisions(model)
	local x = math.floor(mouse.Hit.X / grid + 0.5) * grid
	--local y = math.floor(mouse.Hit.Y / grid + 0.5) * grid
	local y = 4
	if y <= 4 then
		y = 4
	end
	local z = math.floor(mouse.Hit.Z / grid + 0.5) * grid
	model:SetPrimaryPartCFrame(model.PrimaryPart.CFrame:Lerp(CFrame.new(x,y,z) * CFrame.Angles(0, math.rad(rotation * rotationDegree), 
		0), speed))
end

Ask if you need more info.

Thanks for the help!

#2

This is because you have the function after the while wait() do. Move the function to before it.

#3

Thank you, is there an explanation; from what I know is it because the code is running order and while true do just blocks rest of the code? Also why do I get an error when I try to cancel, is there a way to check and block the error:

The error: attempt to index nil with ‘Touched’

function CheckCollisions(model)
  if model ~= nil then
  	local collisionPoint = model.PrimaryPart.Touched:Connect(function() end) --this is the error
  	local touchingParts = model.PrimaryPart:GetTouchingParts()
  	canPlace = true
  	for i = 0, #touchingParts do
  		if touchingParts[i] ~= nil then
  			if not touchingParts[i]:IsDescendantOf(model) and not touchingParts[i]:IsDescendantOf(character) then
  				canPlace = false	
  			end			
  		end
  	end
  	collisionPoint:Disconnect()		
  end
end

function CancelPlacement()
   part:Destroy()
end