Terrible Service from Travelstart

On the 4th june i made a car rental booking with waiver for excess and was successfully completed. I then got an sms from Travelstart stating that my flight has been amended and that the they have sourced another flight. I agreed to the new times and told them that they would also have to change my car hire to meet the changed times. I got confirmation for the new flight and car hire but when i enquired about the waiver for the excess which costed me over R700 they stated that i had no cover. They charged my credit card for the wavier of the excess but now they are stating i never paid for it. I contacted TravelStart call centre who stated that they do not book the car hire but offer it as a service. If you offer a service make sure you have the correct people in your call centre to deal with those issues. I was sent from Travelstart call center to the card booking call centre and none of them are helpful in assisting me. Terrible service and i recommend that people be very careful in using their company. Might have cheap flights but i rather pay more and get good service which is not the case.