Airtel Modem — extra charges

Address:

Delhi

Sir
It is submitted that my modem has been repaired by Universal Telecom & Traders on dated 14/12/12 vide invoice No. 1421. As per airtel rules the visiting charge should be Rs. 150 and other repair charges. But the said company has been changed which already paid by me total Rs. 824/- ie given below:
1. 110 TC 1 repaired (1) Rs. 275, 2. Line Cord (2) Rs. 60, 3. 5V adaptor (1) Rs. 199, 4. Coil Cord (1) Rs. 40
5. Visiting Charges Rs. 150, 6. Inst. Charges Rs. 100

we are using internet continuously by Airtel then why Installation charges taken and secondly 5V adaptor (1) Rs. 199, which is local with highly prices. It is therefore requested that may kindly be taken suitable action and correction regarding said amount.

Waiting for response,
Thanking You
Sushil Kumar Parmar