Airtel — I lost 27gb data in one night without using it

I'm using sorrel postpaid since from 5 to 6 moths... And I'm not using my data and it has been rolled out for months and it is of 22gb as per January month. But all of a sudden it all vanished without any notifications...when I'm calling to customer care they are not responding properly all they keep on saying that I have used all my data in one day... How can I use my 22gb in one night without turning on mobile data... When I'm calling they customer care number... Their automatic voice it self telling that I have 27.5gb unused data and it is giving options to convert my data to rewards... If I used my data so y it is keeps on telling the same... When I ask them the same question there is no proper answer...i have never missed paying any bill... I want my data back