Air India — Refund of Air Flight Tickets

I cancelled my Air India ticket on 28 March. I was informed I will get the refund within 21 days.
It’s been more than 40 days and still the refund has not been credited to my bank account. I am being told waiting for more 10 days, wait for more 3 weeks etc.
Now they saying my money was transferred on 10June. But there is no amount refunded in my credit card. I am being charged every month by my credit card company. The total amount was 42, 939. I am being charged by credit card plus they keep mentally harassing me by not giving the right information.