Expected ')' (to close '(' at line 1), got <eof>?

script.Parent.MouseButton1Click:Connect(function()
	local plr = script.Parent.Parent.Parent.Parent.Parent
	local chr = plr.Character
	
if plr.PlayerOwnsTheMaskPass.Value == true then
	local newmask = script.Parent.TOKYOGHOULMASK:Clone()
	newmask.Parent = chr
	newmask.Mask.Weld.Part1 = chr.Head
script.Parent.Text = "Remove"
script.Parent.removefunc.Disabled = false
script.Disabled = true
else
	script.Parent.Text = "You do not own this gamepass!"
	local market = game:GetService("MarketplaceService")
	local id = 7538706
	market:PromptGamePassPurchase(plr,id)
	wait(4)
	script.Parent.Text = "Tokyo Ghoul Mask"
	end
end)

I click it and then it works but the console comes out with

Players.LegoUnicornRoblox.PlayerGui.CharacterCreation.GamepassFrame.TokyoMask.r:8: Expected ')' (to close '(' at line 1), got

and the remove function stops working

script.Parent.MouseButton1Click:Connect(function()
    local plr = script.Parent.Parent.Parent.Parent.Parent
    local chr = plr.Character

if plr.PlayerOwnsTheMaskPass.Value == true then
    local newmask = script.Parent.TOKYOGHOULMASK:Clone()
    newmask.Parent = chr
    newmask.Mask.Weld.Part1 = chr.Head
script.Parent.Text = "Remove"
script.Parent.removefunc.Disabled = false
script.Disabled = true
else
    script.Parent.Text = "You do not own this gamepass!"
    local market = game:GetService("MarketplaceService")
    local id = 7538706
    market:PromptGamePassPurchase(plr,id)
    wait(4)
    script.Parent.Text = "Tokyo Ghoul Mask"
	end
    end
end)

You forgot the parameter Player. Next time when you are making an event even if you don’t use the parameters you should still include them.

Here is your script fixed:

script.Parent.MouseButton1Click:Connect(function(player)
    local plr = script.Parent.Parent.Parent.Parent.Parent
    local chr = plr.Character

if plr.PlayerOwnsTheMaskPass.Value == true then
    local newmask = script.Parent.TOKYOGHOULMASK:Clone()
    newmask.Parent = chr
    newmask.Mask.Weld.Part1 = chr.Head
script.Parent.Text = "Remove"
script.Parent.removefunc.Disabled = false
script.Disabled = true
else
    script.Parent.Text = "You do not own this gamepass!"
    local market = game:GetService("MarketplaceService")
    local id = 7538706
    market:PromptGamePassPurchase(plr,id)
    wait(4)
    script.Parent.Text = "Tokyo Ghoul Mask"
    end
end)

You can ask clarification anytime.