Save as... reverts to old name when it's reopened.

Using a mac with most up to date acrobat. After I edited a pdf I used save as... to save a new file with a new version number upped by one digit. When I reopened this pdf it reverted to the original name at the top of screen. I had to go to properties/description and change the name there too. I hope this can be fixed so the description updates with a name change.