Ford Focus in warrant with 5 clutch replacements but Ford doesn't want to replace.

Since the original clutch on my Ford Focus Ambiente Powershift, the car has had 4 clutch replacements. I sent the car in on 16/05/2017 for the 5th clutch on 90403km. To date Ford has had the car at the garage with all sort of excuses. They even had the right part box with the wrong part in it. I took the car back and informed Jaco at Imperial Ford Diepriver to phone me when he has the right part. He never ever phones back even though I phone him often. He claims the he is fighting with Ford about the replacement. The vehicle is now on 106000km and I still can't get the car booked in for the clutch replacement or service. Ford is now saying that the car wasn't serviced with them for the 100 000km service and don't want to replace the clutch. The car went in at 90403km well before the 100 000km service. How can I get Ford to do a service make some money but refuse to do the clutch under warranty? They have extended the warranty for 2 years or 80000km but it is clearly a factory fault and will have to keep extending the warranty and keep on replacing clutches every 10 - 15000km or else I will have to take the legal way.