Ola Money — Ola postpaid

On 4th November I booked an Ola ride but after reaching to location driver took otp and ended the ride immediately and I was charged Rs.109 through Ola postpaid for the service which I dint use. Immediately I raised a complaint to Ola and they offered a coupon to use on next ride though I asked for a refund and not a coupon as in order to reddem the coupon I am supposed to book another ride. So I refused for the coupon and asked for a refund. Since there was no action on the complaint and request so I did not clear the Ola postpaid due.

Why should I pay the money, which I never used it