NEED HELP!!!!!!!! 10 POINTS FOR BEST ANSWER!!!!!!!!!!!!?

ok my dad keeps on complaining that every time that he gets a text message, it only rings once. He has the Blackjack II. how do I fix this problem cause sometimes just to know if he got a text message, he has to constantly look at the phone... he wants the message ringtone to ring more than once like in 30 seconds later. let it ring again to remind him.