How long are my files kept on the Free plan?
24 hours from when you added the torrent. Free seedboxes are shared, so they clean themselves up: every torrent is removed 24 hours after it was added, finished or not, together with the files it downloaded. A download that hasn't finished within 2 hours is removed sooner — unless it stopped because your storage filled up, in which case it's kept until the 24-hour mark so you can free space or upgrade. The cleanup runs every few hours, so a removal can come a little after those marks, never before.
So download what you want to your own device within 24 hours: in My Drive, right-click a file or folder and download it (a whole folder comes down as a ZIP — see below). If you'd rather keep files in the cloud, upgrade: your files and unfinished downloads carry over, and paid plans have no cleanup — your files stay for as long as your plan is active.
More on removals: My torrent disappeared or was removed on its own.

