One-time backup does not appear as an option to Restore

I did a one-time back of 6 database of our Exchange server, after backup was completed, none of the databases have a restore date when this one-time backup was successfull. Backups were done via USB external drives, I can catalog and verify with no errors. Not sure why I do not get a Restore option to the date I did my one-time backup. Has anyone experienced this before or have a solution?.

Thanks