Bot opens asynchronously on webhook

Question

I deployed the bot on heroku, when using the webhook, it causes asynchrony, that is, I start the parser and while the parser is running, I can’t continue to use the bot, and if I use long polling on heroku, I can start parsing and continue to use the bot. How can I fix a possible problem in the webhook settings??

TOKEN = os.getenv('BOT_TOKEN')
bot = Bot(token=TOKEN)
dp = Dispatcher(bot)

HEROKU_APP_NAME = os.getenv('HEROKU_APP_NAME')

# webhook settings
WEBHOOK_HOST = f'https://{HEROKU_APP_NAME}.herokuapp.com'
WEBHOOK_PATH = f'/webhook/{TOKEN}'
WEBHOOK_URL = f'{WEBHOOK_HOST}{WEBHOOK_PATH}'

# webserver settings
WEBAPP_HOST = '0.0.0.0'
WEBAPP_PORT = os.getenv('PORT', default=8000)


async def on_startup(dispatcher):
    await bot.set_webhook(WEBHOOK_URL, drop_pending_updates=True)


async def on_shutdown(dispatcher):
    await bot.delete_webhook()


@dp.message_handler()
async def echo(message: types.Message):
    await message.answer(message.text)


 if __name__ == '__main__':
    logging.basicConfig(level=logging.INFO)
    start_webhook(
        dispatcher=dp,
        webhook_path=WEBHOOK_PATH,
        skip_updates=True,
        on_startup=on_startup,
        on_shutdown=on_shutdown,
        host=WEBAPP_HOST,
        port=WEBAPP_PORT,
    )