In the early hours of January 29, as the crowd swelled near the Sangam nose at the Maha Kumbh Mela, a stampede broke out, killing 30 people and injuring at least 60. Even as families continue to search for their loved ones or mourn them, the ghats are thronging with people again. Mayank Kumar reports on the tragedy, the response, and how lessons have not been learned from the past