Did not fulfill service policy

I extended my service plan for a 5 year policy or 60000km . When i bought the car. The reason being don't do alot of mileage . But now I get told I used all the services as I did the 4years or 60000km service . But the book clearly states 60 months or 60000km. Not the number of services . And if you miss an annual service the warranty becomes null and void. *****. Why would I extend it with lower mileage if I wasn't going to get all the services....