Add previously deleted users

Hello - I'm having challenges re-adding users who were previously deleted.  Previously we had the system set to delete users if they were inactive for 365 days as we were only able to manually identify those who left the organization.  We've now addressed that and are managing user data via CSV upload.  There are a number of employees who were inactive and thus were deleted, but still with the organization and should be re-added.  When they try to log in now, even through they are included on our CSV file, they receive an error message that their account has been deleted.  Do I need to manually add them and re-activate them myself?