SBIcard — Incorrect fee charged for rewards redemption not involving any physical gifts but only credit entry or e voucher

I can see that sbi cards has incorrectly charged redemption fee of Rs.99 and gst which is incorrect.These are never chargeable against e vouchers or repayment of bill and what they are doing is simply cheating.There is no physical gift involved and so nothing should be charged.SBI CARDS has started illegal practices nowadays against public policy.
i had never been charged these on any earlier occasions.As for gifts it is ok since there is a courier charge but for simple entry and e vouchers there is no fee or cost at all then how can redemption fee plus gst be charged?
SBI CARDS check all earlier redemptions.There was no fee involved at all.
Kindly get the charges reversed.SBI CARDS is following a wrong policy against public interest.I shall also complain to the RBI