Their fault, nut we have to pay?!?!?

Yesterday my husband has made a booming online for both of us to travel from india to south africa. He spelled our names to the call center guy. When we received our tickets via mail, the guy has made a mistake, and has dropped one of the letters in my surname. When we called them today, they said they have to cancel the tickets and refund us the full amout, and we have to make the booking again. They agreed that it was their fault.. now that we have to make the booking again the next day, the price has gone up with R400 and they expect us to pay the new price.. regardless of the fact that it is not our fault. What bad and unproffessional service! Will never book with them again!!