Infinite yield possible?? what am i doing wrong?

So i made a morph script where you click a button on a GUI to weld the parts to your character and its not working it's popping up this error:

Infinite yield possible on 'Workspace.HannahToots:WaitForChild("UsingMorph")'

Also the error is on line 13.

"Stack Begin Script 'ServerScriptService.MainScript', Line 13 Stack End"

-- [[ SERVICES ]] --
RS = game:GetService('ReplicatedStorage')
SS = game:GetService('ServerStorage')

-- [[ SIDE VARIABLES ]] --
Remote = RS:WaitForChild('MorphRemote')
Morph = SS:WaitForChild('Morphy')
-- [[ MAIN SCRIPT ]] --

function MorphHandler(Player) -- player is automatically a given variable
    local Character = Player.Character or Player.CharacterAdded:Wait()

    if Character:WaitForChild('UsingMorph').Value == true then
        Character.UsingMorph.Value = false
        for _,limb in pairs(Character:GetChildren()) do
            if limb:IsA('BasePart') then
                limb.Transparency = 0
            end -- check children class
        end -- loop
        -- delete morph
        if Character:FindFirstChild('Chest') then Character.Chest:Destroy() end
        if Character:FindFirstChild('Arm1') then Character.Arm1:Destroy() end
        if Character:FindFirstChild('Arm2') then Character.Arm2:Destroy() end
        if Character:FindFirstChild('Leg1') then Character.Leg1:Destroy() end
        if Character:FindFirstChild('Leg2') then Character.Leg2:Destroy() end
    elseif Character:WaitForChild('UsingMorph').Value == false then
        Character.UsingMorph.Value = true
        for _,limb in pairs(Character:GetChildren()) do
            if limb:IsA('BasePart') then
                limb.Transparency = 1
            end -- check children class
        end -- loop

        local modelname = Morph:Clone()

    if Player.Character:findFirstChild("Humanoid") ~= nil and Player.Character:findFirstChild("Morphy") == nil then
        local g = modelname.Chest:Clone()
        g.Parent = Player.Character
        Plr.Character.UsingMorph.Value = true
        local C = g:GetChildren()
        for i=1, #C do
            if C[i].className == "Costume" or "Union" then
                local W = Instance.new("Weld")
                W.Part0 = g.Middle
                W.Part1 = C[i]
                local CJ = CFrame.new(g.Middle.Position)
                local C0 = g.Middle.CFrame:inverse()*CJ
                local C1 = C[i].CFrame:inverse()*CJ
                W.C0 = C0
                W.C1 = C1
                W.Parent = g.Middle
            end
                local Y = Instance.new("Weld")
                Y.Part0 = Player.Character.Torso
                Y.Part1 = g.Middle
                Y.C0 = CFrame.new(0, 0, 0)
                Y.Parent = Y.Part0
        end

        local h = g:GetChildren()
        for i = 1, # h do
            h[i].Anchored = false
            h[i].CanCollide = false

        if Player.Character:findFirstChild("Humanoid") ~= nil and Player.Character:findFirstChild("Leg1") == nil then
        local g = modelname.Leg1:Clone()
        g.Parent = Player.Character
        local C = g:GetChildren()
        for i=1, #C do
            if C[i].className == "Costume" then
                local W = Instance.new("Weld")
                W.Part0 = g.Middle
                W.Part1 = C[i]
                local CJ = CFrame.new(g.Middle.Position)
                local C0 = g.Middle.CFrame:inverse()*CJ
                local C1 = C[i].CFrame:inverse()*CJ
                W.C0 = C0
                W.C1 = C1
                W.Parent = g.Middle
            end
                local Y = Instance.new("Weld")
                Y.Part0 = Player.Character["Left Leg"]
                Y.Part1 = g.Middle
                Y.C0 = CFrame.new(0, 0, 0)
                Y.Parent = Y.Part0
        end

        local h = g:GetChildren()
        for i = 1, # h do
            h[i].Anchored = false
            h[i].CanCollide = false
            if Player.Character:findFirstChild("Humanoid") ~= nil and Player.Character:findFirstChild("Leg2") == nil then
        local g = modelname.Leg2:Clone()
        g.Parent = Player.Character
        local C = g:GetChildren()
        for i=1, #C do
            if C[i].className == "Costume" then
                local W = Instance.new("Weld")
                W.Part0 = g.Middle
                W.Part1 = C[i]
                local CJ = CFrame.new(g.Middle.Position)
                local C0 = g.Middle.CFrame:inverse()*CJ
                local C1 = C[i].CFrame:inverse()*CJ
                W.C0 = C0
                W.C1 = C1
                W.Parent = g.Middle
            end
                local Y = Instance.new("Weld")
                Y.Part0 = Player.Character["Right Leg"]
                Y.Part1 = g.Middle
                Y.C0 = CFrame.new(0, 0, 0)
                Y.Parent = Y.Part0
        end

        local h = g:GetChildren()
        for i = 1, # h do
            h[i].Anchored = false
            h[i].CanCollide = false

if Player.Character:findFirstChild("Humanoid") ~= nil and Player.Character:findFirstChild("Arm1") == nil then
        local g = modelname.Arm1:Clone()
        g.Parent = Player.Character
        local C = g:GetChildren()
        for i=1, #C do
            if C[i].className == "Costume" then
                local W = Instance.new("Weld")
                W.Part0 = g.Middle
                W.Part1 = C[i]
                local CJ = CFrame.new(g.Middle.Position)
                local C0 = g.Middle.CFrame:inverse()*CJ
                local C1 = C[i].CFrame:inverse()*CJ
                W.C0 = C0
                W.C1 = C1
                W.Parent = g.Middle
            end
                local Y = Instance.new("Weld")
                Y.Part0 = Player.Character["Left Arm"]
                Y.Part1 = g.Middle
                Y.C0 = CFrame.new(0, 0, 0)
                Y.Parent = Y.Part0
        end

        local h = g:GetChildren()
        for i = 1, # h do
            h[i].Anchored = false
            h[i].CanCollide = false


    if Player.Character:findFirstChild("Humanoid") ~= nil and Player.Character:findFirstChild("Arm2") == nil then
        local g = modelname.Arm2:Clone()
        g.Parent = Player.Character
        local C = g:GetChildren()
        for i=1, #C do
            if C[i].className == "Costume" then
                local W = Instance.new("Weld")
                W.Part0 = g.Middle
                W.Part1 = C[i]
                local CJ = CFrame.new(g.Middle.Position)
                local C0 = g.Middle.CFrame:inverse()*CJ
                local C1 = C[i].CFrame:inverse()*CJ
                W.C0 = C0
                W.C1 = C1
                W.Parent = g.Middle
            end
                local Y = Instance.new("Weld")
                Y.Part0 = Player.Character["Right Arm"]
                Y.Part1 = g.Middle
                Y.C0 = CFrame.new(0, 0, 0)
                Y.Parent = Y.Part0
        end

        local h = g:GetChildren()
        for i = 1, # h do
            h[i].Anchored = false
            h[i].CanCollide = false


    end -- check if using morph
end -- function end
end
end
end
end
end
end
end
end
end
end

-- [[ CONNECTIONS ]] --

Remote.OnServerEvent:Connect(MorphHandler)

What am i doing wrong? I've checked in play mode the "UsingMorph" value is in the character from the GUI giving it to player on click but still the error shows up.