Sold the incorrect vehicle. Faulty discs

I bought a new VW Polo Vivo 1 Dec 2014. On 9 Jan 2015 i was contacted and told i had received the incorrect vehicle as they did not check the vin number upon hand over. My \new"second hand vehicle came with an already 1906ks on the clock. In February/March a shudder started with the brakes. I called to book my 1st service and was told they will check the shudder at the service.(no mention of the expired warranty) I took my car in at 6 months 15000ks on the clock. I was messaged 10 minutes before my car was ready i could come and collect and my new discs were on(without confirming with me) and covered with my warranty. i was then messaged 10 minutes later to be told i was not covered and would need to pay an additional R2229"