Make only one player able to touch a part with Touched event?

I attempted to make a part that only one player can touch, and no one else can take that one player's spot until he leaves the part.

Example (what i'm trying to make it look like); Auto Duels pads, Custom Duels pads.

I've been trying and researching for hours but I couldn't find a solution.. What's the problem?

I'm new to scripting and my knowledge is really low, if you could explain in a sample of code that would be appreciated!

 local Part = script.Parent
    local alreadyin =  {}
    local db = true

    Part.Touched:Connect(function(hit)
        if not db then
            return
        end
        db = false
        if hit.Parent:FindFirstChild("Humanoid") then
            local player = game.Players[hit.Parent.Name]
            if alreadyin[1] == nil then
                table.insert(alreadyin, player.Name)
            end
            for i,v in pairs(alreadyin) do
                if v == player.Name then
                    Part.Color = Color3.fromRGB(0, 255, 255)
                    Part.TouchEnded:wait()
                    alreadyin[1] = nil
                    Part.Color = Color3.fromRGB(163, 162, 165)
                end
            end
        end
        db = true
    end)