Bad service lephalale Avis

We hired a car from Avis car Hire in lephalale, ellisras, Onverwacht and they suggested that we pay for another day the Friday 14/09/2018. We were coming back on the 13/09/2018 in the evening and they said that they are not there during the evening but need to pay for the Friday also. We did that. On the Friday morning they phoned us at 9 o.clock and said why is the car not back ? We said but we paid for the Friday also and they rep**** that for the Friday it should have been back 8:30..... We responded by taking the car promptly back , but they then charged us for the Saturday for two drivers and also took the car. We tried reasoning with them but the lady simply said that she told us it should be back at 8:30 ? We requested the managers number but she simply gave us a helpline that is unmanned number.