Volkswagen - After car service face problem of brake disc vibration

“bought volkswagen polo model December ****, last * years my experience was wonderful. Last month I had serviced my car at Rewari volkswagen workshop. But after service i faced problem of break disc. After lodging complaint I visited to Volkswagen Rewari workshop. First their attending behaviour is very different against last time visit at time of service. Behave me like a culprit why I am complaint to Volkswagen team for service related issue. then one person of mechanical team take drive test with me and accepted issue is genuine if apply break at high speed above ** kMPH. And then service supervisor Mr. Sahil asking me that break disc is damaged and will repaired and it will cost Rs **** and will paid by you. I Asking him during service break pad and Disc was ok and also there is no problem before service. Then He say we can't do nothing in this matter and all will be charged by you only or otherwise you can go somewhere for this. On day of service as I seen as a layman the car washing and dry cleaning not done properly and they also accepted it on the same day. and when I run the car at high speed say above ** KMPH then face the problem of disc. I can't under that before service there was no issue in disc and during service inspection there was no any abnormality in disc as they recorded and then how disc got damaged after got it to me and as I found it when run car on highway at high speed. Note: After Service not a single issue resolved. Pls suggest and do needful to resolve the issue. Now they refused to do anything. HR** AC ****(car number)”