I have a new computer and needing to setup my SourceTree access to my BitBucket repo. But when I try to connect via HTTPS (I don't have SSH setup) it says I should login using my username instead of an email address. But when I login to BitBucket.org in a web browser, I login using my email address. There is no indication that there even exists a username for the account.
Why am I experiencing this strange error? It won't let me connect!