Ariva rental ********** way of doing businesd

I had a 2015 Renault Capture, which I handed back and payed all outstanding fees, now about 5 weeks later they send out the blue a final warning with me apparently still owing them 10000 Rand for damages, when the vehicle was returned there was no damage not allowed by the contract, I was not handed any checklist alltough I asked to do one and was assured that is not necessary, is this the way how businesses operate nowadays and rip us as consumers off totally. No notification not description of apoarant damage only all of sudden a email from pre legal. Folks don't ever deal with these sharks please they are the worst kind of *********.