Might just be a glitch. Could also be a reason for it. I can't really be sure.

I'd submit a support ticket. They're very good with those.

You should get a response within an hour or two. Might be different, though, if it's a glitch in their systems and it's billing related.

In case you didn't know, submitting a Support Ticket is really easy.

From your control panel, click the support tab found on the left. Then click the "Open a Support Ticket" button in the top right corner. Just fill out all your information, leaving the Affected Droplet as is (since it's not a Droplet you're having issues with), and you'll be good to go!

I hope this helps you,

Have a great day.