NOKIA MUSIC EXPRESS
No proper functioning of the phone

Hi i purchased a nokia 5220 music express in December and within a few months of purchase i have been having software problems wherein the screen goes blank n i have to switch the phone off and then switch it on before it starts to function again. but now since this morning of 15th September the earpiece has stopped working and in order to hear the other person on the line i have to either use the headset or i have to turn the phone on loudspeaker..what should i do?? please advice promptly..thank you