There was no error, the print's usually appears, Why doesn't my character fly?

It should fly when you press 2 times space and stop with 1 time, but it does not work.

local player = game:GetService("Players").LocalPlayer
local mouse = player:GetMouse()

function GetMassRecursive(p)
    local mass = 0
    for i,v in pairs(p:GetChildren())do
        if #v:GetChildren() > 0 then
            mass = mass + GetMassRecursive(v)
        end
        if v:IsA("Part") then
            print(v.Name)
            mass = mass + v:GetMass()
        end
    end
    return mass
end

local wDown = false
local sDown = false
local isFlying = false
local speed = 10
local U = game:GetService("UserInputService")
Player = game:GetService("Players").LocalPlayer
local running = false
local s = ""
local on = game.ReplicatedStorage.Events:WaitForChild('FlyOn')
U.InputBegan:connect(function(key)
if key.KeyCode == Enum.KeyCode.Space then
    s = s.."w"
    print('UnFlying')
    local tool1 = player.Character.UpperTorso
            local tools = {"Anti-Grav", "FlyingVelocity"}
            for i,v in pairs(tools) do
    local tool = tool1:FindFirstChild(v)
    if tool then
        tool:Destroy()
player.Character.Humanoid.PlatformStand = false
isFlying = false
    end
end

        delay(0.2,function ()
            if s ~= "ww" then
                s = ""
            end
        end)
        if s == "ww" then
        print('flying')
                if isFlying then
            speed = 0
            wait()
            speed = 10
            local f = Instance.new("BodyForce")
            f.Name = "Anti-Grav"
            f.Force = Vector3.new(0,196.2,0) * (GetMassRecursive(player.Character))
            f.Parent = player.Character.UpperTorso
            local v = Instance.new("BodyVelocity")
            v.Velocity = (mouse.Hit.p - player.Character.UpperTorso.Position).unit * 10
            v.P = 100
            v.MaxForce = Vector3.new(math.huge,math.huge,math.huge)
            v.Name = "FlyingVelocity"
            v.Parent = player.Character.UpperTorso
            player.Character.Humanoid.PlatformStand = true
            isFlying = true
        end
    end
            if key.KeyCode == Enum.KeyCode.W then
        wDown = true
    end
    if key.KeyCode == Enum.KeyCode.S then
        sDown = true
    end
end
end)
U.InputBegan:connect(function(key)
    if key.KeyCode == Enum.KeyCode.W then
        wDown = false
    end
    if key.KeyCode == Enum.KeyCode.S then
        sDown = false
    end
end)

local MAX_SPEED = 500
local MIN_SPEED = 0
spawn(function()
    while player.Character.Humanoid.Health > 0 do
        if isFlying then
            local r = 1+(speed/500)
            player.Character:SetPrimaryPartCFrame(CFrame.new(player.Character.PrimaryPart.Position,mouse.Hit.p)*CFrame.Angles(math.pi/r,math.pi,math.pi))
            player.Character.UpperTorso.FlyingVelocity.Velocity = (mouse.Hit.p - player.Character.UpperTorso.Position).unit * speed
            if wDown then
                speed = speed + 5
                if speed > MAX_SPEED then
                    speed = MAX_SPEED
                end
            elseif sDown then
                speed = speed - 5
                if speed < MIN_SPEED then
                    speed = MIN_SPEED
                end
            end
        end

        game:GetService("RunService").RenderStepped:wait()
    end
end)