You can't grow within the company. I've worked for the company for almost two years. I tried move up into the marketing department but all they do is turn you away. I also tried to work in QA and they preferred to hire people that worked in the company for one month than someone who has been with them for almost two years. They don't want you to advance. They need people on the phone and they will keep you there.
If you're looking for a part-time job because you're in school, find somewhere else to go. Trust me, you can find something that pays better and treats you better.