We really lost money at Kulula.com

I placed a booking via a phone. It was confirmed. I called a few days later to change a return flight, which was changed and I even confirmed with the call center agent that there will be no charges incurred. To my surprise the day I tried to check in the was a problem with the ticket I made changes on. Which ended up spoiling my flight to Cape town. Now I was stranded at the airport. Looked like a fool. I had incurred petrol charges. I didn't even get emails that said you owe a fee. I only got check in emails that's all. I was really unfairly treated.