Gamepass prompting a purchase, but not changing my variable to do other stuff. How do I fix this?

So, I am trying to make it so when you click a button, it checks if you have the gamepass, and if you do then it runs some code. and if you don't have the gamepass, it prompts you to buy it. my problem is that when you accept the prompt and you buy the gamepass, it does not change my assigned variable to run the rest of the code. Is there a fix for this?

Here's my full code. it's in a localscript.

local btn = script.Parent
local fr = btn.Parent.Parent.changeLicenseKey
local win = btn.Parent.Parent

local mps = game:GetService("MarketplaceService")

local gamePassId = 25727086
local hasPass = false

local function promptPurchase()
    local plr = game.Players.LocalPlayer
    hasPass = false

    local success, message = pcall(function()
        hasPass = mps:UserOwnsGamePassAsync(game.Players.LocalPlayer.UserId, gamePassId)
    end)
    if not success then
        warn(message)
    end

    if plr then
        if hasPass == true then
            print("Player already owns gamepass "..gamePassId)
            print(gamePassId.." gamepass is owned by "..game.Players.LocalPlayer.Name)
            win.top.appName.Text = win.top.appName.Text.." - Choose A License Key"
            fr.Visible = true
            btn.Parent.Visible = false
        else
            mps:PromptGamePassPurchase(plr, gamePassId)
            print("Gamepass not owned")
        end
    end
end

btn.Activated:Connect(function()
    promptPurchase()
end)

mps.PromptGamePassPurchaseFinished:Connect(function(plr, id, successBuy)
    if successBuy and id == gamePassId then
        hasPass = true
        print("hasPass = true")
    end
end)

Thanks!