Billed 5600 when I have a maitainace plan

I bought a new car with VW Woodmead, was then adviced to take a maintainace plan. After 6mnths my speak rubber got loose. When I took in the car for service due I was then told the maintainace plsn doesn't cover since I up graded the car which was never done(its not on record) but I choose to let go. About 3weeks ago I had a break down. I contacted VW and they towed the car. The car was diagnosed and told my clutch is falty. Again I was told maintainance doesn't cover. Then I was billed 5600. Paid that since I was desparate for the car. Then a week later I booked in he car for service again(which my 5600 invoice bill vanished) VW told me the maintainance plan doesn't cover park light and petrol filter. I then called Avis which in the maintainance plan company. I spoke to charls, he said he doesn't cover the filter and bulb cause I went above service interval by 220kms but they do cover machenical problems like \clutch"&amp"