hs battery in less than 3 months

the battery is very poor, to avoid. in less than 3 months it does not take the load and is out after 15 minutes. contacted the manufacturer, who offered me 5 compensation. a joke, the warranty is one year, it must be replaced or fully reimbursed. amazon I contact to find out what I can do. has avoided at all costs. I do not understand how Amazon keeps the seller on his website.