Using classic Outlook for Windows in business environments
I got something similar. Subject line: Don't miss your unsettled payment.. blah blah. The From address shows my own email address. That is spoofed. This group of spammers can't hack so they write a story to extort you.
There is no breach. It's just an annoying junk mail. Delete and be done with it.
If you're paranoid, change your password. Otherwise, treat them like spam... don't open them. Delete.