Lenovo Thinkpad — non replacement of product under warranty

I had lodged a complaint with the company about the battery of my laptop which was not working properly and was under warranty then . I lodged the complaint on 12th of August , 2010 . The battery was under warranty till the 2nd of October , 2010 . The complaint was made from Ranchi but they told me that as they did not have any service centre in Ranchi , the complaint would be dealt with in Raipur which was their nearest service centre to Ranchi . I then called their Raipur service centre the next day but the people there had no imformation about the complaint . Sometime after this , I came to know that the complaint has been cancelled . They told me that I had cancelled the complaint but I never did so . After this I called about 20 times between September and December but I never got any satisfactory reply from their side . On 3rd of January I told them my problem and they relogged the complaint and told me that the battery would be replaced under warranty only . But again yesterday I received a call from Lenovo support centre and was told that the battery cannot be replaced as the warranty has expired . They further told me that I should have contacted them earlier . Sir , if you check the call records , you will find that I have called them atleast 20 times if not more . I was also given an email i.d . There also I have forwarded my probem 6-7 times but never got any reply . Now they tell me that nothing can be done . Please help .