Stripe - Error when testing live payment

Howdy,

I've been testing Stripe in its test environment, and all has been well. Today, I switched over to the live environment, and tried a test payment. That didn't go so well. After submitting my CC info, I got this error: "No such plan: 1_1; a similar object exists in test mode, but a live mode key was used to make this request."

What do I need to do to fix this?

Thanks!

-aj