I will tell you following steps to use HDFC Bank, PayZapp App so that it would be easy for you to have Tata Sky recharge.

Process to use
Open PayZapp App

Click on 'Scan to Pay'

Press the yellow button to see the QR code Displayed on TV

Scan & enter the amount. Confirm payment

Pay in One Click using your linked Debit/Credit Card

Offer Details
Offer is valid only if you "Pay with PayZapp" Provided customer is registered for PayZapp at the time of transaction.

Get 50% additional Balance on Tata Sky with mVisa (Scan to Pay)

Offer valid for first 6 lakhs transactions using BharatQR/ mvisa via PayZapp or 30th September 2017 whichever is earlier.

Each Tata Sky subscriber ID can avail the offer once every calendar month during the offer period.

Max Additional Balance available per Tata Sky Subscriber Id per transaction during the promo period is Rs. 100

Additional Balance amount shall be credited to respective Tata Sky account for which the recharge has been done.

Address:-
HDFC Bank
1st Floor,C.S.No.6/242,
Senapati Bapat Marg,
Lower Parel,
Mumbai - 400 013.