McCarthy - Service plan.

I Purchased a 2019 Duster from MccarthyNissan in Randburg. After the finance approvals they informed me that it is actually a 2018 model. I accepted this 'honest mistake' from them and still purchased the vehicle. This purchase included a service plan of 6 years or 90000km (6 services) for R5600. 4 months after the purchase I asked them for my paperwork that the SalesPerson Ishmael was supposed to send to me. On this paperwork they state my service plan is only from 72000km to 90000km (NOT FOR 90000km). That means I paid R5600 to save 1 service with a cost of R1000. In the hype of the car delivery and being in a hurry and because I TRUSTED the Mccarthy brand, I must have missed that in the contract. The problem is that Sunel informed me that I have signed and that it won't be fixed and I am welcome to buy another service plan from them. This is ******* and *********. McCarthy have either on purposed ******* me to sign that service plan or have sold me 1 pre booked service (value of R1000) for R5600.