Source path: app/Channels/TelegramChannel.php
Extracted from supplied specification. Review before copying into application.

<?php
namespace App\Channels;

use Illuminate\Notifications\Notification;
use Illuminate\Support\Facades\Http;

class TelegramChannel
{
    public function send($notifiable, Notification $notification): void
    {
        if (!$notifiable->telegram_chat_id) return;

        Http::post('https://api.telegram.org/bot' . config('services.telegram.token') . '/sendMessage', [
            'chat_id' => $notifiable->telegram_chat_id,
            'text' => $notification->toTelegram($notifiable),
            'parse_mode' => 'Markdown',
        ]);
    }
}
