HTC India — Complaint against htc one e9+ mobile phone

Address:

Gandhinagar, Gujarat, 382007

Hello,
I am a loyal htc customer, since 2012 i been using just htc mobiles, i been totally satisfied from htc side till previous experience. But with my present mobile "htc one e9+" which i bought on 9/2/16, i m continuously facing a single issue agn and agn tht 'rear camera glass is catching dust frm inside', whn i purchased piece rear camera glass was already gaining too much of dust making camera picture quality weak. I am too fond of clicking pics and its 20mp camera was one of the biggest reason i choose this phone. I took the phone to htc mobile service "shyamal branch, ahmedabad" on 23/4/16 they got me rid of dust and i was in comfort. But aft 2-3 days past again the rear camera glass was catching dust from inside. As days past it gradually increased n making the glass opaque (Not clear). Agn i took the phone to the same service station 10/5/16 i narrated thm the issue thy agn clean tht glass n thy promised tht this issue will b not faced agn, but thing is same pls help m tired need solution as soon as possible