async def run_client(client):
   async with client:
       await client.start()
       await client.run_until_disconnected()


async def main():
   accounts = await dbworker.get_accounts()
   sessions = []
   for account in accounts:
       sessions.append(run_client(TelegramClient(StringSession(account[2]), config.app_id, config.app_hash)))
   sessions.append(dp.start_polling()) # добавил только это
   await asyncio.gather(*sessions)


if __name__ == '__main__':
   asyncio.run(main())