Ola Cab — harassment for the last 4 months asking for payment which I don't owe to them

Address:

New Delhi, Delhi, 110027

Sir,
I have travelled from coimbatore airport to ottapalam on 19th april and paid rs. 2600/- which were appeared on the meter.
I am getting call & sms on daily basis for an additional amount of rs.1500 saying that this is for postpaid charges. I am not a post paid customer & i never used ola money. I booked this travel thru your airport kiosk. I want you to stop calling me.
Thanks... Lalitha-nair [protected]