Greedy and ********* Audi Brynston

i Have the Worst experience of my life with Audi Bryanston. everytime i service my car with them, i have to always take it back few days Later. currently i paid just above 43k of which they Quoted to Fix The Mechatronics"which was according to them the only Problem", on the day i fetched my car i Raised a concern about the sound my car Engine was Making, the engineer said He couldn't hear the difference, i drove out and came back 5 minutes later and i raised the issue about my MMI Not working they took it in but i Drove Back again this time My Bluetooth wasn't working. The incompetence of not double checking their work once done is shocking. 2 days later My my clutch was was on and off. one minutes its working the next its not. i took the car Back. they Refuse to fix it. instead they want me to pay for their incompetence. charging me for the same thing twice.