Ola Cabs / Ani Technologies — Pickup issue

I have book pre-schedule cab 8 yrs before for Delhi T3 airport drop. I was alloted ride 15 mins before the schedule and after that driver approached me to ask that he can't come for ride. Even he didn't cancel the ride thereafter I cancelled that as I was getting late for my flight due to tight schedule. Thereafter one after another 3 rides I booked and ride alloted though all drivers refused to come for pickup.This is not first time it's happening with me during earlier ocassion I face this issue.

But this time I almost lost flight and ultimately I arrange a driver who agreed to drop thru my private car. Surprisingly just before my leaving several private taxi drivers approach me for ride...how they come to know that I have a ride book from OLA.

This experience was quite frustrating and I have decided not to book any ride from OLA atleast for airport drop as it's not reliable at all.