Amazon India — Product shows delivered but not received

I ordered one product like Sound Bar from Amazon India. Seller Appario Retail.
The product was unfortunately shipped by India Post and that was the biggest mistake. Looks like Amazon's own delivery system was not able to deliver to my pin code!

The issue is on 18-Oct I got a message from India Post that the parcel is out for delivery. However thruout the day it was never received.

Late night I got a call that the parcel has been delivered around 8:25PM to the addressee.
This is strange because I never received it. No one came at my door. I also checked if my mistake the postman left at security. But it's not there too.

India Post tracking status shows delivered. When contacted amazon, they said this could be a technical glitch, however no one in Amazon is able to tell me what is their policy on wrong deliveries!
What if item is delivered by mistake to someone else and that person has freely accepted it as a free lunch!
While amazon said they will lodge a complaint if it really happens, this is overall disappointing

1. Do not use India Post. The government office is not honest and genuine
2. Have clear policies on such exceptions, what if the item gets wrongly delivered to someone else