Leaving a customer to blame " unethical"

The company I work for owns a JMC Carrying that I drive on a daily basis, I took the vehicle in for a service (30 000km) when I needed to present the service book I discovered that it wasn't in the vehicle, normally I check after services unfortunately on my stupidity I never received or checked if it was there thinking it would of been put back. So now when it went in for a service and to have the power steering repaired, to get a call saying that there is no record of our previous services nor records of the company and that the company I work for is liable for all cost. We have never received any copy of paperwork from them once the service was complete and because there isn't a service book in the vehicle now we have no actual proof needless to say that there is a box full of service books that other customers haven't been given. The vehicle is 10 months old and basically been for a service every 3 or so months. The previous time there was a problem too when they said that they can't pick up the vehicle but I mustn't worry it will be sorted out which clearly wasn't. When my company purchased the vehicle and I had collected the license plates about 7 days later only once I too it for the 3000km service was it discovered that they had given me the wrong license disk and plates basically 2 months later.

The vehicle has been now at the dealer for a week ( since the 18th of July 2019 till now 25th July 2019) they have given us a new service book and I was witness to them stamping the new book with kilometers for the services since I wrote it all down in a book for personal record the, KM, Date, diesel still in tank and how KMs I've done so far on the tank. Now JMC SA is basically calling myself and the company liars and that they wash their hands on the matter and we the customer are fully liable for all costs and that our warranty is also nil and void due to disorganized paperwork and bookings. I just got the impression that someone hadn't done there job correctly and now the customer has to suffer which is seriously no right in so many ways. It's disappointing to receive service like this considering that myself who drives the vehicle daily is very impressed with the capabilities once loaded, compared to other brands with less of a load. I enjoy the vehicle it is just unpleasant to have to deal with a company that indirectly blames the customer for the entire issue when they played a huge role in the problem too.