Norton Utilities 16 transfer to replacement computer

I purchased Norton Utilities 16 online with download for three computers.  One of these needed to have the hard drive replaced.  I downloaded both Norton security and Norton Utilities 16 when after I got my pc back with a new, empty drive.  There was no problem with Norton Security - it recognized the subscription immediately.  However, the Norton Utilities 16 appears to be a trial version and I don't  have an activation code.

How can I get Norton to recognize the change on Norton Utilities?

 

Mike Monsen