misleading

I reported a strange sound on my Polo vivo and was told to take the car to vw for diagnosis.after diagnosing,vw Newcastle quoted me a stripping fee of r5200 that I had to pay as innovation dsnt cover for the stripping of the gearbox,as they told me the sound came from the gearbox.innovation group told vw they are waiting for my authorisation for stripping before they continue with anything.why was I not told when taking a policy that they don't cover for certain things?i