Public Sector Insurance Co. — Car fare was paid but ola is asking for money.

I was traveling to Delhi IG airport from nearby Delhi. I booked ola for travel and paid him money at airport but I don't know what he did. After few days I got message for post paid payment and then I tried to get help from customer care. Ola customer care is not responsive and don't give any information on asking questions.
Now ola is trying to scare me and says for legal action against me. It is unfair because it looks like the drive did something unfair against me. I want help on this.