How should I prepare for my interview at Sprint?

[Tamilee]

i got a call today from sprint asking me to come in next tuesday for an interview, and its got me worried. about two years ago i applied, and got the call to come in, and they had me take a simulation test, then i spoke with a woman in HR who explained she would look at my results and give me a call back. i never got a call, but i did get an email explaining that they filled the position, and thanked me for my interest. i had quit at&t about two months before that and worked for them about a year and a half. people kept telling me to keep trying, that it can be hard, but everytime i applied back, i just got an email telling me that they thanked me for my interest in their job, but i wasn't what they were looking for. i have no idea what they are looking for; although i've been trained to work as a customer service represenative in a cellular phone call center, and that it states on their website that you will be trained, i'm just afraid i won't get the job. i have an associates degree in general studies, and i've taken several computer classes. i also have my CNA certification, and a CPR certification, as well as my Med Tech license, but these things have nothing to do with customer service or customer sales. i want this job soooooo bad. help me!