Incorrect Service plan added to vehicle finance

I purchased a pre owned vehicle Toyota Aygo through FNB in Feb last year with just over 14000km on the odometer. In April I was contacted by Innovasion Group affiliated with FNB and they sold me a service plan for 30 000 - 60 000 km. In february this year my Wife took the car for it's first service since we bought it. The dealership then informed us that the service plan on the vehicle is incorrect as the vehicle had already with the previous owner, been serviced annually for the 30 000 and 45 000km service. This basicaly meant that the service plan sold to me for 3 services was only good for one service. Innovation Group has not provided me satisfactory solution to this. The total of the service plan is R 12 743-80 and they are only willing to offer me the 75 000km service with no reduction in my service plan fee (sold me 3 services and now only providing me 2) or upgrade it on my cost to include the 90 000km, which was not part of my original financial planning this year. Please assist me to resolve this? <div><br></div><div><em>(Supplier name changed from First National Bank to Wesbank by Hellopeter.com)</em></div>