Exide Battery — Service charge claimed by exide battery for under gurratee period replacement which is 30% of original cost

I had purchased exide battery for my two wheeler 26 oct 2023. I complained for not working proper. Dealer checked and confirmed replacement is required uner guarantee period. I have replaced battery and they claimed for 250 rs service charge. This charge is @30% of battery purchased. Even when we r buying new battery they do not charge any amount. This charges r not part of their policy and they r also not informing customer while providing guarantee card. This amount is on much higher side and i strongly belive that I am not liable to pay the same. Kindly look into it and ensure fair competition for customer. Customer care also didnt responded with documents and informed to pay charges. Receipt is also available with me.