my simulator script to increase players size have errors and does not work help..?

game.Players.PlayerAdded:Connect(function(player)
    player.CharacterAppearanceLoaded:Connect(function(character)
         local humanoid = character.Humanoid
         humanoid:WaitForChild("BodyDepthScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("BodyHeightScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("BodyWidthScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("HeadScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid.WalkSpeed = 16 * (player.leaderstats.Weight.Value / 250)

         player.leaderstats.Weight.Value:GetPropertyChangedSignal("Value"):Connect(function()
         humanoid:WaitForChild("BodyDepthScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("BodyHeightScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("BodyWidthScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid:WaitForChild("HeadScale").Value = .5 + (player.leaderstats.Weight.Value / 250)
         humanoid.WalkSpeed = 16 * (player.leaderstats.Weight.Value / 250)
        end)
    end)
end)

this is my script first it does make me small when i start but i cant move also there is a error saying something like index property change signal nil