There's a banner added to the top of the label page @patchparlor :
"Please be aware that UPS, eBay Send, USPS are experiencing issues at the moment. We apologize for any inconvenience and if affected, ask that you try again later."
These things are usually fixed within a few hours, though we've seen it take 'til end of day on occasion. Impossible to say unless eBay provides an update.
For USPS and UPS you can purchase labels at pirateship.com at comparable rates as an immediate solution. Unfortunately, that's not going to help you with shipping eBay Standard Envelope.
Hopefully it's fixed soon and, at minimum, you can get labels printed today even if you're not able to ship until tomorrow.
