Are you still under contract with them? If not, go elsewhere. Straighttalk will let you buy your own phone elsewhere then connect up with them. And it's way cheaper with no contract. I moved there a few years ago and never skipped a beat.
I believe you may have gotten a rep more concerned about his/her commission than actual service of his/her customer. I'm on their website and can buy outright but have to hit the link to do so as it defaults to payment plans.