for a while now my hero hasnt been alerting me when i get a text message. sometimes im textin my friend and i will be waiting for a text so i unlock my phone to see if i got a text and then it will alert me i got a text and on the text it says i got the text for example at 7:15 but i wont get the alert or see it at 7:19.... any 1 got an idea what can be wrong with it?