RopeConstraint wont work with Character, why?

I made this rope swinging script, using rope constraints. But whenever I shoot the rope I get stuck midair, unable to move. I have no idea why. Any help please?

--// Variables

local players = game:GetService("Players") 
local plr = players.LocalPlayer

local char = plr.Character
local head = char:FindFirstChild("Head")

local athA = Instance.new("Attachment") 
local athPart = game.Workspace.AttachPart --This is a specific part that the rope attaches to
local athB = Instance.new("Attachment")
athB.Parent = athPart 
athA.Position = Vector3.new(0,0,-1)
athA.Parent = head
local length 
local uis = game:GetService("UserInputService")
isSwinging = false

--// Functions:

uis.InputBegan:Connect(function(key) 
    if key.KeyCode == Enum.KeyCode.R  then
        if isSwinging == false then
            isSwinging = true
			script.WebSound:Play()
			wait(0.1)
            rope = Instance.new("RopeConstraint")
            length = (head.Position - athPart.Position).magnitude
            rope.Attachment0 = athB
            rope.Attachment1 = athA
            rope.Length = length
            rope.Visible = true 
            rope.Parent = head
	    --  I have tried adding a HumanoidStateType here
        end
    end
end)

uis.InputEnded:Connect(function(key)
    if key.KeyCode == Enum.KeyCode.R then
        if isSwinging == true then
            rope:Destroy()
            isSwinging = false
            --  I have tried adding a HumanoidStateType here
        end
    end
end)

To figure out the process of whats going on make sure you double check by playing the character and then looking if the attachment is there or not, a simple bug can be easily fixed if you look hard enough. I'm guessing you just didn't name the attachment 0 or one. Example

local athA = Instance.new("Attachment")
local athPart = game.Workspace.AttachPart
local athA.Name = "Attachment0"