When going to /settings/usage/ inside Prismic, it says 94903100 % of your limit used.
This seem to be an error, as the legends shows Included: 1 B, which I think means 1 byte.
But we are on the Starter plan which includes 100 GB of bandwidth.
Thank you for raising this - you're right, it's a visual bug on our side. We've logged it and are working on fixing it. I'll add your post to the ticket, so we can come back and let you know when it's fixed 
Your actual usage/allowance within your plan is not impacted by this at all, it is just the display that's bugged. If you want to know more about your usage and this bug is preventing that, feel free to reach out to support.