ServerScriptService.Size:4: attempt to index nil with 'Humanoid' - roblox

Question

Cant figure out what the problem is
while wait(.5) do
local children = game.Players:GetChildren("Humanoid")
for i = 1, #children do
local hum = children[i] .Character.Humanoid
hum.HeadScale.Value = children[i].leaderstats.Points.Value/50 +1
hum.BodyHeightScale.Value = children[i].leaderstats.Points.Value/50 +1
hum.BodyWidthScale.Value = children[i].leaderstats.Points.Value/50 +1
hum.BodyDepthScale.Value = children[i].leaderstats.Points.Value/50 +1
hum.WalkSpeed = children[i].leaderstats.Points.Value/3.12
hum.JumpPower = children[i].leaderstats.Points.Value
hum.MaxHealth = children[i].leaderstats.Points.Value+25
end
end
was trying to get a simple size script to work.

Answer 1

The attempt to index nil with Humanoid error is telling you that the object that you are trying to grab the Humanoid out of doesn't exist. This line specifically :
local hum = children[i].Character.Humanoid
When a player joins the game, there is an indeterminate amount of time before their character model actually spawns into the world. So between when they join and when their character spawns, the Player.Character property is nil.
Your code does not handle the possibility that the character model is nil, and you are trying to access the humanoid immediately.
A safer approach is not to use a loop, but to observe changes to the leaderstats values and react to those changes. So in your code that creates your leaderstats objects, do something like this :
local Players = game:GetService("Players")
local function updateCharacter(hum : Humanoid, points : number)
local bodyScale = (points / 50) + 1
local walkSpeed = points / 3.12
local jump = points
local health = points + 25
hum.HeadScale.Value = bodyScale
hum.BodyHeightScale.Value = bodyScale
hum.BodyWidthScale.Value = bodyScale
hum.BodyDepthScale.Value = bodyScale
hum.WalkSpeed = walkSpeed
hum.JumpPower = jump
hum.MaxHealth = health
end
Players.PlayerAdded:Connect(function(player)
-- when a player joins the game, give them a leaderstats folder
local leaderstatsFolder = Instance.new("Folder")
leaderstatsFolder.Name = "leaderstats"
local pointsValue = Instance.new("IntValue", leaderstats)
pointsValue.Name = "Points"
pointsValue.Value = 0 -- or load from dataStores
leaderstatsFolder.Parent = player
-- listen for changes to the points and resize the character
pointsValue.Changed:Connect(function(newValue)
-- escape if the character doesn't exist
local character = player.Character
if character then
updateCharacter(character.Humanoid, newValue)
end
end)
-- when the character model spawns into the world, update it immediately with the player's point size
player.CharacterAdded:Connect(function(character)
updateCharacter(character.Humanoid, pointsValue.Value)
end)
end)