At the end of each season, the videos created that year are archived.
All your videos from previous years (except free videos) can be watched in My Creations as long as you have an active Magic Pass. Use the year selector at the top of My Creations to find them.
On the website, only some creations load at first: click View more at the bottom of the list to see the rest.
Free trial videos are deleted at the start of February, and free birthday videos 30 days after the birthday.