renting a car via randgo for durban july 2015

I booked two cars in February 2015 via randgo in jhb when we get to Durban we were promised we will get two cars and we must produce licenses and ref numbers for our bookings and credit cards for payment when were get there no cars where available and we were stranded and one of their staff offered us one car we tried to pay they said the car was booked under a company don't know how and they gave us a car and when we return the car we gave them keys and wanted to pay still they insisted that the car was paid and now they want their money after 7 months which I don't have a problem with what I hate is when im getting threatened by legal actions and that they will contact my employer their staff was suppose to make sure before handing a car as per contract they take the cards in case of damages and for rental but they were negligent they didn't number 2 we booked for two cars instead of them giving us two alternative cars since the polos were not available they left us stranded for about 2hours and later they gave us one car which on their statement is more expensive than the two we booked and now they threaten me with legal and to contact my employer for my personal trip