1mg - Package not delivered

I checked the medicine required for my mother in *mg and as it showed delivery within *-* days, so I placed the order on the **th of Oct, **** as I needed the medicine on an urgent basis.
Now the ordeal began. The shipment was of
EcomExpress. It arrived my town, Guwahati on ** Oct, ****, however for * days till ** Oct there was no delivery attempt. On **th evening, I suddenly got the message that my order couldn't be delivered as my address was undeliverable. But, this was the same address where *mg delivered my last ** orders.
Till now for this order *mg has revised * delivery dates but the order still couldn't be delivered. And above all there is no customer care help. There is no where I can call, there is a useless chat service where never one finds an agent to discuss the problems and if I send a mail, the only reply given to me is an automated one assuring me to look into the matter.
I am not buying any fancy thing, I am buying critical healthcare medicine on which person's life may depend. If this so called online pharmacy fails to deliver my order even after ** days how can one depend upon them.