All your previously generated videos can be found in the History tab located in the bottom left corner of the workflow and generation pages.

Within the History panel, you can scroll down and select the video you would like to access or edit.

The History button is available on the generation page too.

You can also access the History section by clicking on the ≡ (menu button) on the top left and navigating to History

Clicking on → Show more will give you a full list of previously generated videos!