Karbonn Mobiles
Price list for service were not published

Dear Sir,

I am Kiran Kumar, last year I bought a Karbonn mobile at bangalore, now mobile have a software problem i am unable to open my message inbox. as my native is Tirupati i visited Tirupati Karbonn mobile service center (SV CELLULAR), i explained problem they took one hour time to resolve the issue and charged 150/rs (without receipt) but problem was not resolved and they ask again 350/rs for another software update.

i denied and asked the price list for service charges . they declined to give the same and said bill also not possible for the same.

unfortunately there is no price list mentioned in the Web also.

My question is

Why payment bill not issuing by the authorized service center?

why service price list is not mentioned in the service center?