Hi @Miguel_Peres! @RyanE is right, you should be able to remove them from your Team following these steps: https://asana.com/guide/help/organizations/members#gl-remove-from-team
But I would also advise you to remove them from your Organization following the steps outlined in this post Team Members Who Are Deleted Are Still Showing - #2 by Marie
Let us know if you’re still running into trouble! 