audi s3 clutch slip

[S3_Ren]

hi everyone i'm a new comer,
i've have just bought a Audi S3 on a 52 plate with 51k on the clock with 12 months warranty from a main audi dealership in shrewsbury, having only had the car for 10 days and only done 800 miles in it and the clutch has started to slip, so i called the dealership and told them the problem i was having, instead of them helping they said its not covered under warranty and said they've done a pdi check on it before i bought the car so it down to my driving or wear n tear, and i would have to pay to put it right.

i need some advice from you on what to do next? because they are treating me like a mug?