Ola Cabs / Ani Technologies — extra fair charged

I booked a cab from my friend's phone. The fair was 29 rs when it was booked. When i reached home, i asked the driver how much it was. He took five minutes to tell me the fair, he said it was processing. He held two phones and i dont know what he even did. But when he showed his phone the fair was 57 rs. How is this even possible? Ola is cheating on people easily. Registering a comment may not help us but people should be aware about this too so they can raise their voice if this happens to them.