HDFC Bank — credit card annual charges against offer made

Address:

560066

I'm pawan kumar and i'm using hdfc regalia first credit card. I took this card a couple of years back (Maybe 2-3). I contacted hdfc customer care in aug 2018 for some issue and at the end of the conversation i was told about an offer. I was told that if i activated any smart pay service (Automatic bill payment) with my card and used for at least 3 months then my card would become lifetime free card. I had activated that service for my mobile bill payment. Now i have been charged 1000 as annual fee and 180 gst against the promise made to me by one of their customer care executives.
I know that this is a chargeable card but as i was asked to activate smart pay with a promise of lifetime free then it should not have been charged or at least i should have been intimated that the offer/policy has changed.