Bitbucket gives credit to the wrong person for committing

I am using Sourcetree and Bitbucket for version control. Whenever I commit and click Sourcetree and look at it on Bitbucket under recent activity, it shows that I have committed. However, when I go to the commit page of the repository, it says that another employee has committed. The person he demands made the commit for me, used this computer before I did it. I opened a Git shell and typed in Git config user.name, but it showed my name. I can't find any trace of its settings on the Bitbucket account settings page or Sourcetree -> options tools, and I don't know where else to look.