Issue in the project id

Dear all, I have some clarifications regarding projtransposting table. Usually when the projectid is created with a wrong id then we used to rename the projid with the new one.But some of the old re-name created projid with transactions exists in projtransposting table. But the same projid is not in the projtable. How it will be possible that the projid have been re-named but still the old transactions exists?