Samsung Galaxy Y — less battery backup

Address:

Srinagar, Jammu and Kashmir

i purchased samsung galaxy y,i am facing problem with battery back up.since this phone is 3g N 2g i get 4hours battery back on 3g and 5 hours on 3g.i wad informed this phone carries 12 hours battery back up.
secound concern is i sometime find no option in mobile for call end i tried several short cuts but call get stuck and it gets rectified only if i.restart my mobil.
regards
shahid
[protected]@yahoo.com