Audi SA not honouring Service Plan

I purchased AUDI A3 SEDAN 1.4T FSI MANUAL – October 2016. In August 2017 it went for it first service 15 000 km at Audi Centurion. On 29 January 2018, 6:00 pm I experienced issues whilst driving. My car refused move when in gear. I called Audi customer care, & they agreed to have the vehicle towed away to Audi Centurion. On 31 January 2018, I received a phone call from the service advisor from Audi Centurion, explaining they assume the clutch is damaged. And they require me to accept a quotation of R7 000 in order for them to proceed to diagnose. I refused to accept any quotation as this is clearly covered in the Service Plan. I reviewed the Service Plan in detail, & it clearly doesn’t exclude Clutch damages. Secondly the car only has +- 17 000 km, therefore this could have being factory faults. To date my car is still at Audi Centurion where they refuse to repair it. Formal letter was received from Audi SA stating they don't cover clutch damage. This matter has being to referred MIOSA(Motor Industry Ombudsman of South Africa) for resolution. I truly regret purchasing a AUDI, knowing that I've being a Mercedes owner for 12 years...