Ola Cabs — Cancelled booking from their end without prior intimation

Address:	Hyderabad, Andhra Pradesh, 500082
Website:	OLA CABS

I have booked an advance booking (1day before, booking no. CRN[protected] Ola cab from IIT, Hyderabad. Without any prior notice they have cancelled my booking and after conversation with customer care got to know that there is no cabs in my area, they requesting me to choose some alternative way.
Then What is the **** use of the advance booking system.
It's really a BS service they are providing.
Don't believe in Ola, you might face problem if it's very important to reach somewhere.