HDFC Bank — wrong levy charges in credit card account

I have been given Regalia first credit card by HDFC bank in 2015 with an offer of 12 complementary access to airport lounges.

I was given two cards, first credit card and secong priority pass card with an instruction to use priority pass card for visiting airport lounges.

In the month of December 2017, the bank suddenly charged in my credit card for visiting airport lounge.

When i called the customer care, the advised me to use Regalia First credit card instead of priority pass card for complementary access.

When i again visited the lounge in January & February 2018, the bank has again charged for my visits.

Now on being asked, they are telling that such visits to lounges is chargeable.

The bank has never intimated me that the visit to lounge would be chargeable.

Tha bank has also cheated me for with drawing the complementary access to the lounges without any intimation.

Please help and resolve.