I'm confused. What are you are asking for them to do?

You pre-paid for $10k of usage, with an agreement to roll-over unused credits into next year's contract. The plain definition of roll-over includes the fact that you'd have an active future account. Otherwise, they'd just say "prepay credits never expire". Imagine trying to use roll-over minutes on a phone plan where you cancelled the phone.

$1k/yr seems like a very low minimum which will serve as basis to roll your $9k of existing credits into.

Sounds to me like you just didn't think about or budget for this. Doesn't sound like any misrepresentation to me.