How To Despawn A Model When A Player Leaves?

Hello again, sorry for posting back here so soon, but I've ran into another issue.

Essentially, this is a part 2 to a previous post I made regarding the spawns in my game, of which you can find here.

Our game's biggest problem is people spawning in all the robots, and despawning other people's robots. With help from a lovely member on here, that problem has been solved. However we have since ran into a new problem that I thought would be easy to fix, but is far from it.

If a player spawns a bot and then leaves the server, the bot stays in and nobody can despawn it, this can be repeated multiple times and can cause immense lag and disruption in the server.

This is the current script for the spawners:

local Robot = game.ServerStorage:FindFirstChild("Aegis",true) 
local Spawned = script.Parent:FindFirstChild("Spawned",true)

function onClicked(player)

    BotSpawned = player.BoolValue
    BotBeingUsed = player.StringValue

    if Spawned.Value == false and BotSpawned.Value == false then
        BotBeingUsed.Value = 'Aegis'
        BotSpawned.Value = true
        backup = Robot:clone()  
        backup.Parent = workspace
        backup:makeJoints()
        Spawned.Value = true
        script.Parent.BrickColor = BrickColor.new("Really red")
    elseif Spawned.Value == true then
        if BotBeingUsed.Value == 'Aegis' then
            BotBeingUsed.Value = 'None'
            BotSpawned.Value = false
            backup:Destroy()
            Spawned.Value = false
            script.Parent.BrickColor = BrickColor.new("Lime green")
        end
    end
end


while Spawned.Value == true do
    for i, player in pairs(game.Players:GetPlayers()) do
        if player.StringValue.Value ~= 'Aegis' then
            backup:Destroy()
            Spawned.Value = false
            script.Parent.BrickColor = BrickColor.new("Lime green")
            break
        else
            wait()
        end
    end
end


script.Parent.ClickDetector.MouseClick:connect(onClicked)

The part from "While Spawned.Value == true do" and blow is my attempt to fix said issue, however it has yet to be successful, if someone could help me out to fix this one problem, the game's biggest issue can be solved.

I am quite new to this level of scripting, so excuse me if I don't quite comprehend things right/have bad code.

Thank you for reading.