Raycasting isn't working properly?

local tool = script.Parent
local player = game:GetService("Players").LocalPlayer
local Mouse = player:GetMouse()
Debounce = false
pressed = false
cancelled = false
canPress = false

tool.Equipped:connect(function(mouse)
    print("Tool equipped!")

    mouse.Button1Down:connect(function()
        print("Mouse pressed!")

        if Debounce == false then

            Debounce = true     

            local ray = Ray.new(tool.Handle.CFrame.p, (mouse.Hit.p - tool.Handle.CFrame.p).unit * 30)
            local part, position = workspace:FindPartOnRay(ray, player.Character, false, true)

            PreviewPart = script.Parent.Wooden_Floor:Clone()
            PreviewPart.Name = "Preview part"
            PreviewPart.Transparency = 0.5
            PreviewPart.Anchored = true
            PreviewPart.CanCollide = false
            PreviewPart.Position = position + Vector3.new(0, 0.375, 0)--  + Vector3.new(0,part.Size.Y/2,0)
            PreviewPart.Parent = workspace

            customBuild = Instance.new("Part")
            customBuild.Transparency = 1
            customBuild.Anchored = true
            customBuild.CanCollide = false
            customBuild.Name = "CustomBuild"
            customBuild.Parent = PreviewPart

            wait(1)

            canPress = true 
        end
    end)
end)

while wait() do
    if Debounce == true then

            Mouse.Button1Down:connect(function()
                if canPress == true then
                    pressed = true
                end
            end)
            Mouse.Button2Down:connect(function()
                if canPress == true then
                    cancelled = true
                end
            end)

        if cancelled == true then
            Debounce = false
            cancelled = false
            pressed = false
            canPress = false
            for i,v in pairs(workspace:GetChildren()) do
                if v.Name == "Preview part" then
                    v:Destroy()
                end
            end
            print(cancelled)
        elseif pressed == true then
            Debounce = false
            cancelled = false
            pressed = false
            canPress = false
            for i,v in pairs(workspace:GetChildren()) do
                if v.Name == "Preview part" then
                    v.Transparency = 0
                    v.Name = "Floor"
                    v.CanCollide = true
                end
            end
        end
        if PreviewPart ~= nil then
            local list = {player.Character,PreviewPart}
            local Player = game.Players:GetPlayers()
            local mouse = player:GetMouse()
            local ray = Ray.new(tool.Handle.CFrame.p, (mouse.Hit.p - tool.Handle.CFrame.p).unit * 30)
            local part, position = workspace:FindPartOnRayWithIgnoreList(ray, {player.Character,PreviewPart}, false, true)
            PreviewPart.Position = position --+ Vector3.new(0, 0.375, 0)
        end
    end
end

It gives no error (client) it works inside studio fine, the tool is inside replicatedstorage cloned and then putted inside the player, it doesn't go to your mouse position inside a real server, other parts work find.