All healthbar scripts being buggy and wont work?

Every healthbar script i try works fine for the most part, but when i die it doesnt go back to full size when i respawn. It's gotten to the point where im just looking at scripts online and they all still do that

this is the current script im using

-- ScriptGuider
-- Basic custom health bar program from my YouTube video
-- Video: https://www.youtube.com/watch?v=opZtUhwDWE8
wait() -- ROBLOX made me do this.

local Player = game:GetService'Players'.LocalPlayer
local Character = Player.Character or Player.CharacterAdded:wait()
local Human = Character:WaitForChild("Humanoid")

local HealthFrame = script.Parent

Human.HealthChanged:connect(function(Health)
	HealthFrame.Size = UDim2.new(Health/Human.MaxHealth,0,1,0)
end)

it seems that you set the screengui ResetOnSpawn to false that makes the script stop working, try to put the character inside a loop like this or you can set it to true instead

local HealthFrame = script.Parent
local Player = game.Players.LocalPlayer

while wait(0.2) do
	local Character = Player.Character or Player.CharacterAdded:wait()
	local Human = Character:FindFirstChild("Humanoid")
	if Human then
		local Health = Human.Health
		HealthFrame.Size = UDim2.new(Health/Human.MaxHealth,0,1,0)
	end
end