HDFC Bank — hdfc credit card charges - fraud or something phishy?

I always used to pay the minimum balance due of my hdfc credit card.

For the month of jun 2020, my minimum amount due is too high though i have not used my credit card at all for last three four months and i found the below charges under transactions in my statement for the month of may 2020:

Finance charges :some amount charged
Smartemi, int nbr: some amount charged
Smartemi, prin nb: some amount charged

This is a very unacceptable manner of charging interest. It should have been made clear before itself. High interest rate itself is a charge.

How can such deceptive practice be carried out that too in this lockdown period?

I want these charges reversed.

I hope hdfc understand and do the needful.