How to fix listener in Trello and Discord Notifier?

I was creating a Trello and Discord Notifyer when someone buys an item. But when I use the GUI button. It sends a request but the listener doesn't receive it. I don't know why. Below is an Image, scripts and other stuff to help. (Don't mind the Marketplace variable, I didn't get to it yet)

PhotoLink! If it doesn't work: https://gyazo.com/68ca142fe12233e22d4fd4872e532eab

Local Script

script.Parent.Order.MouseButton1Down:Connect(function()
	script.Parent.Purchaced.Visible = true
	game.ReplicatedStorage.PurchaseCrates:Fire()
	print("Sent with the player name of "..plr)
	script.Parent.Order.Text.Text = "Ordered!"
end)

Script in Event

local MPS = game:GetService("MarketplaceService")
local APIModule  = require(game.ReplicatedStorage.WebhookAPI)
local TrelloAPI = require(game.ServerScriptService.TrelloAPI)
local boardID = TrelloAPI:GetBoardID("Testing Product Hub")
local ListID = TrelloAPI:GetListID("New Orders", boardID)
local newWebHook = APIModule.new("489927603705348119","gQfpv9bM2hlTaArDyl54eqfT1kxQXjVW3f6JOCEzqvOzYkCdaMtVU2ouSRDjIuw4oAuh")
local Event = script.Parent
--Signaling
local Players = game:GetService("Players")
Players.PlayerAdded:Connect(function(plr)
	if Event.Event then
			newWebHook:post{
		username = "Purchace Bot",
		content = "@here **"..plr.."** has purchaced crates."
}
	TrelloAPI:AddCard("Name:"..plr,"Purchacing Crates",ListID)
	end
end

Hope someone figures it out because I am stumped.

LS

script.Parent.Order.MouseButton1Down:Connect(function()
    script.Parent.Purchaced.Visible = true
    game.ReplicatedStorage.PurchaseCrates:FireServer()
    print("Sent with the player name of "..game.Players.LocalPlayer.Name)
    script.Parent.Order.Text.Text = "Ordered!"
end)

S

local MPS = game:GetService("MarketplaceService")
local APIModule  = require(game.ReplicatedStorage.WebhookAPI)
local TrelloAPI = require(game.ServerScriptService.TrelloAPI)
local boardID = TrelloAPI:GetBoardID("Testing Product Hub")
local ListID = TrelloAPI:GetListID("New Orders", boardID)
local newWebHook = APIModule.new("489927603705348119","gQfpv9bM2hlTaArDyl54eqfT1kxQXjVW3f6JOCEzqvOzYkCdaMtVU2ouSRDjIuw4oAuh")
local Event = script.Parent

--Signaling--
function onPurchaseFired(player)
	TrelloAPI:AddCard("Name:"..player.Name,"Purchasing Crates",ListID)
	newWebHook:post{
        	username = "Purchase Bot",
        	content = "@here **"..player.Name.."** has purchased crates."
	}
end
script.Parent.OnServerEvent:Connect(onPurchaseFired)
--Signaling--

Not sure if this works or not, but it probably will. Please, spell purchased correctly. That will annoy a few users that want to buy things. Once again, I never tested this. If I made a mistake, let me know and I'll have it fixed tomorrow by this time.

What you did wrong was try checking for a value that most likely will never exist. Firing the server can't be checked for true or false. Also, it only tried checking when a player joined.