I know it’s been a while, and thanks for posting here in the Community forum.
Nest Aware subscription is auto-renewal. If you can no longer access your video history, possible cause are you had an issue with your Nest Aware bill so you have to take the time to check for any potential billing issues. The internet is slow, or you have deleted the history on your own.
Let us know if you have any other questions. We’re happy to help.