Blue Dart Express — product delivery wrong manners

I want to complain about the parcel delivered at my residence yesterday 15 dec 2017, ordered through paytm. Awb no. [protected]

Complaint as follow :

Delivery boy called up for the residence route, my mother was standing at gate and waved him for the route, he came infront of my residence gate. Packet was already out. He threw the packet at my mother's hand. He not even stood up from the bike and came towards gate. Distance between bike and out residence gate is about 5-5.5 fts. My mother is having back pain problem and when he threw the packet, she disbalnced. He said sorry, but this is not the way of deliverying the parcel.
I need explaination with this incidence. Who will be responsible if something had happend to my mother?

Thank you.
Vrushali mukherjee
+91 [protected]