Time to do this: 1 minute
This is almost always a permissions issue or a password-has-been-recently-updated issue.
If you get this message after your Flow has been running fine for a long time, it’s likely password related. If you’ve updated your Flow account password recently, just add a new connection to your Flow so that it re-grabs your credentials. Then everything should resolve and your Flow should run again.
In your Flow run, you’ll see “Unauthorized” as the failure message.