How do you tag people with BillboardGui?

So I want this to make it to a billboardgui gets cloned into a players head but has to be listed in a backpack. But the script keeps breaking, and i dont know why.

local pln = script.Parent.Parent.Parent
local pl = game.Workspace:FindFirstChild(pln.Name)
wait(0.1)
local plh = pl.Head
local pltn = script.Parent.Players:FindFirstChild(pln.Name)
wait(0.1) -- Whenever I use a :WaitForChild command, I use a interval in case its too fast.

if pltn == nil then
    print(" Player" .. pln.Name .. " does not have a tag. Showing nil.")
end
if not pltn == nil then
    local pltnn = pltn.Value
    local plt = script.Parent.Tags:FindFirstChild(pltnn)
    wait(0.1)

    if plt == nil then
        print(" Player" .. pln.Name .. " has a value, but assigned tag does not exist. Showing nil.")
    end
    if not plt == nil then
        local tag = plt:clone()
        tag.Parent = plh
        print("Player" .. pln.Name .. " has obtained tag " .. pltnn .. " successfully.")
end end

the value i want it to pick up is a stringvalue named the player and the value as the tag name.

Explorer Image