You found out that the clock starts when you enter a new product key.
Had you renewed your old product under it's key. The days would have merged.
You could have downloaded an installer of your current / old product via https://manage.norton.com/ on to your new computer and use the remaining subscription days.
If you contact Norton Support maybe thay can work some magic for you.
Are you still running your old computer.
You still need to go to https://manage.norton.com/ and verify your new product is recognized.
Respectfully
