When I die in the game, a large number of errors appear. Why does this happen?

When I die in the game, a large number of errors appear. This started happening after the update of roblox studio. The errors are very primitive and I do not understand why they appear. Here are the errors:

19:17:38.310 Players.ZaharKor12.PlayerGui.Gui.Levels.Exp.LocalScript:8: attempt to index nil with 'TweenSize' - Studio

19:17:38.311 Players.ZaharKor12.PlayerGui.Obby.Frame.Mail.Time.LocalScript:13: attempt to index nil with 'Text' - Studio

19:17:38.448 Players.ZaharKor12.PlayerGui.Gui.Market.ScrollingFrame.TextLabel.LocalScript:5: attempt to index nil with 'Text' - Studio

19:17:38.862 Players.ZaharKor12.PlayerGui.Teleport.EasyLevel.ObbyTokens.TextLabel.LocalScript:4: attempt to index nil with 'Text' - Studio

19:17:38.863 Players.ZaharKor12.PlayerGui.Teleport.NormalLevel.ObbyTokens.TextLabel.LocalScript:4: attempt to index nil with 'Text' - Studio

19:17:38.864 Players.ZaharKor12.PlayerGui.Teleport.HardLevel.ObbyTokens.TextLabel.LocalScript:4: attempt to index nil with 'Text' - Studio

19:17:38.864 Players.ZaharKor12.PlayerGui.Teleport.InsaneLevel.ObbyTokens.TextLabel.LocalScript:4: attempt to index nil with 'Text' - Studio

19:17:38.865 Players.ZaharKor12.PlayerGui.Gui.Market.ScrollingFrame.Frame.GemsTime.LocalScript:16: attempt to index nil with 'Visible' - Studio

19:17:40.863 HttpError: ConnectFail - Studio

Here's one example:

local player=game:WaitForChild("Players").LocalPlayer
while true do
	task.wait(1)
	script.Parent.Text=player:WaitForChild("leaderstats").Tokens.Value
end

And here's the mistake:

Players.ZaharKor12.PlayerGui.Teleport.EasyLevel.ObbyTokens.TextLabel.LocalScript:4: attempt to index nil with 'Text'