Axis Bank — unable to close my uncle and aunts credit cards

My uncle and aunt were having received their credit cards from axis bank which has not been used for long time. But still Axis bank is adding annual charges and adding interest to those cards.
My uncel and aunt were not that educated to look into these things as people from bank polished them to sell their credit cards.
Now I tried to reach customer care to get the cards close their is no way since they were asking fro registered mobile no which has been lost on aircel problem and i am very much frusted over the response on the phone customer care.