I was new to scripting and I was trying to make a script where the player change team, the billboard gui changes too, but I can't seem to figure it out.

This is a ServerScript inside a ServerScriptService

local ServerStore = game:GetService("ServerStorage")
local TeamService = game:GetService("Teams")

game.Players.PlayerAdded:Connect(function(player)
	player.CharacterAdded:Connect(function(char)
		for i, v in pairs(game:GetService("Players"):GetChildren()) do
			if v.Team.Name == "Free Stalker" then
				local tag = ServerStore:FindFirstChild("FreeStalker"):Clone()
				if tag:IsA("BillboardGui") then
					tag.Parent = char.Head
					tag.TextLabel.Text = player.DisplayName
				end
			elseif v.Team.Name == "Team _" then
				local tag = ServerStore:FindFirstChild("ToBeChangedTeam"):Clone()
				if tag:IsA("BillboardGui") then
					tag.Parent = char.Head
					tag.TextLabel.Text = player.DisplayName
				end
			end
		end
	player:GetPropertyChangedSignal("Team"):Connect(function()
			if char:WaitForChild("Humanoid").Health == 0  then
				for i, v in pairs(char.Head:GetChildren()) do
					if v:IsA("BillboardGui") then
						v:Destroy()
					end
				end
			end
		end)
	end)
end)