In sourcetree, try editing your account settings (gear icon next to "find repositories" dialogue) and make sure your Bitbucket account details are entered correctly. I had this problem and it was because my Bitbucket password had not been stored.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.