pay back my money *******

I bought a ticket on line for my sister and indicated on the ticket request that she would have a child on lap. today intercape refused to let my sister in the bus with her toddler and refused to refund my money. this is a clear theft and *****. they held her ransom to buy a ticket for the toddler or get out of the bus. I tried to reason with the consultants and the manager at the parkstation but in vain. my nephew had travelled on the same bus 2 weeks back and he was never required to pay. I did not cancel the ticket, intercape refused to let my sister in the bus, I paid but they refused to deliver. I WANT MY MONEY BACK! DO NOT BE CALLING ME PLEASSE JUST PAY MY MONEY! I WILL NEVER USE THIS BUS AGAIN, IT IS A VERY VERY BAD SERVICE. WOULD NOT RECOMMEND IT TO ANYONE. THE MANAGER AND THE BUS DRIVERS ARE JUST WORSE