We're currently investigating elevated error rates with the API starting at 23:25 UTC. This is only impacting Connect account creation and updates, and it is safe for users to retry failed requests. We'll post an update soon.
From 2019-06-03 23:25 to 2019-06-04 01:30 UTC we experienced elevated errors and some incorrectly rate limited requests with the API. The issue is now resolved and any affected requests can be safely retried.