Policy nr QB/SO/***

I took out a service plan on my car Golf Citi Rox the first service being on 150 000 km. I asked the sales person if I can service the car in December and he said yes as soon as the first installment is done i may service the car any time that suits me. I never recieved the documentation over e-mail so on the 7th december i phoned to request it again. Customer care then informed me that i may only take my car in for servicing end of January after 3 installments. This was not the agreed upon terms. I specifically asked about this it was answered to me differently. Why would I pay for a service plan where i end up paying for the service itself out of my pocket. Can i please get assistance on this matter, or assistance in canceling this contract as it doesn't benefit me giving you my money for nothing at the end of the day.