The plugin uses email to match Bitbucket user and commit author. So, there will be no entries if the email associated with Bitbucket user doesn't match the email of the commit author.
Bitbucket doesn't show emails of commit authors in UI so it may be required to clone the repository and use git commands like like git log or or git config user.email email to show user email.
For example, clone the repository locally and then use use git show command command:
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Possibly the user configured the wrong email address in his local git setup, correcting this address will solve the issue for future commits.
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