[Resolved]  Pure It Water Purifier(Hindustan Unilever) — auto switch off not working

I have bought pure it water purifier on 10th feb.2009.i use it singally (around 4 litres of water filtered everyday).its battery life indicator started declining in only 5 months o[censored]se & was completely RED around NOVEMBER 2009, and since then it has been passing (i dont know that without battery how it is filtering) water.
please hear to it.