Anyone else having this issue today (11/20/18)? It says they're temporarily unavailable but it's been this way the last couple of hours. We have signed in and out and it is still occuring.
Out systems did experience an issue earlier today with shipping labels being temporarily unavailable which would have caused the issues you were experiencing. This has since been resolved, so you should be able to purchase labels if you're not doing so already!
When outages like this occur, we do our best to get our status page updated with any information we have surrounding the issue. I'd recommend keeping our status page bookmarked and signing up for text notifications so that you'll be well equipped should another outage occur that can impact your day to day workflow.
Let me know if you have any questions!