Cancel Bus Ticket

Last Sunday, actually i bought a bus ticket ( Konsortium ) from Ipoh to KL. Just after i bought, my friend told me he also want to come back and can fetch me together. Then i feel better follow my friend's car.
Since i bought the ticket, but i try to go back to the ticket counter to cancel it. Luckly, i able to cancel it, but only can refund 50%. Thats ok, better than nothing.