Hero Motocorp — Damage battery

Hi, am abhinav mishra from sultanpur u. p.. i had bought a super spelender in june month of 2015 from mahaveer agency sultanpur u. p., and my byk battery is not working now so for that am visit showroom of mahaveer hero and query about warenty but they reply me only one year warenty is vailid from purchase date... but in manual book battery warenty period is given up to 18 month and if byk is not run up to 20 thausand k. m in this cause warenty period is applicable.. according mannual codition my byk is still run only 9000km. and purchase perioud is only 13 month so why warrenty is not applicable according mannual book? please revert me on my mail or on my mobile number.. [protected]@gmail.com, [protected]