Asus India — Asus zenfone 2 display issue

Address: 500088

HI,
Myself thej working in infosys bought asus zenfone2 2 months back, in an accident the display has damaged and i took to regenersis store in hyderabad. they took 5400 for display and gave it ome, it looked good for 2 days and after that it just fell from my hands into sand from feet, thats it the so called gorilla glass has broke as if a car was ran over it, i belive those asus store guys doesnt wore original gorilla glass. i took again and they said again i need to pay 5400 rupees, what the is this. the mobile itsekf is 10000 and it repair costs 12000.what wrong with asus india service to the customers.i want an answer.
As i need my mobile again i agreed to pay 5k to them and submitted the phone.
5400 costs gorilla glass simly broke if in fell on sand...what quality does asus india is maintaining i didnt understand..please look into it...this is crazy...hate u asus :(