HDFC Bank — Automatic one assist activation through loan on credit card

Address: 411028

I have activated a my moneback platinum credit card in around last week and i found that 1299/- rs was debit and i had the other mail which states that i have taken loan of 1299/- rs loan on 1.5% interest for 3 months (Smartemi they call).
Why this service is even started? And how my payment is decided through smartemi?
I dont want this service at all.
I called oneassist they said they will call me in next 48 hours, activation was done keeping customer in dark so why cancellation is taking so much time.
And will cancellation charges will be applied?
My details
Name swapnil warke
Your oneassist relationship number : 2232110
Valid upto : 12/06/2018
Mobile no. : [protected]

To hdfc,
Please dont apply such services by default or with silent note
If cancellation charge is applied that is customers loss. These kind of thing will build some bad reputation
Please revert on this.