My iphone 5S 16GB stopped charging.The problem repeated in 7 months after got a replaced handset.

Had purchased a iphone 5S 16 GB in march 2014.In November 2014 phone stopeed charging & battery started draing upto 0%.Apple service provider dignosed the issue & replaced me with a new handset as it fall within warranty period.Now the same problem occurred on 25/7/2015.When visited Apple service centre of Ahmedabad/Gujarat/India,3-4 other Apple cusomers were there with same problem.The service engineer replied evevryone with same answer that you all have power socket problem & you need to replace the handset as it is nonrepairable.Now they quoted me INR 23600/ as replacement estimate.That's utter non-sense.