Maxx Mobile Mt 250 — very poor battery charging amp;wifi

i was purchased maxx mobile model # MT250 at this month of august 2011 and recommended me to battery charging atleast 4 hours in first charge , i charged more than 4 hours mobile shown charging full than removed it and insert the sim cards and making phone setting operated just half an hour , and mobile shown battery is one point low of total three points and i surprised it battery is fully low and going to automatically switched off within three hour total i try again and again that result is same as above and i return to the vendor they are irresponsible answering to be taken as serviced it also same complaint
so i required to you what is the solution for my problem ? i hope that you will take responsible answer ....?