Skoda India — skoda rapid battery failed

I bought skoda repid in feb 2018 and now my battry total fiald they told me you added other assecries from outnof market thats why your battry faild and they ask me for 8500 for new battry... I have other 2 cars and same and more thing i added in that cars but thay battry still working good so skoda give me bed type of battry... I bought 2 same car same day from tourqe skoda ahmedabad... Mr vaibhav service advisor told me that...!!! My car wireing is totaly parfact but thay dont want to check... I have to add accssirois form market coz skoda ahmedabad dont keep that all in store so we dont have any other option