Your publication drafts are on the Publications page of your profile, at uni.xyz/profile/edit/your-username/publications. Set that page's filter to Drafts and everything you have started but not published is listed there. Select a card and the editor reopens where you left off.
A draft has no public page
Drafts are private to you. They are not listed at uni.xyz/publications, they are not on your profile, and nobody else can open one. The public publication address serves published work only, so a draft's link returns not found even when you are the author. The Publications page of your profile is the only route back in.
Nothing clears out old drafts. The editor saves as you type, about two seconds after you stop, and a draft then stays where it is indefinitely.
Editing a published publication turns it back into a draft
This is the cause nobody guesses, because it involves no draft control at all.
Step one of the publication editor saves everything as a draft, including work that was already published. Open a live publication, change a word in the title or the description, and the autosave moves it out of Published and into Drafts. Its public page stops opening. Selecting Next at the end of step one does the same thing.
Nothing on screen warns you, so the first sign is usually that your own link has stopped working, or that a publication has appeared under Drafts on its own.
The fix is to finish the trip through the editor rather than closing it. Continue to step two, Publishing Details, and select Publish again. The publication and its address come straight back. If you opened it only to reread it, publish it again anyway, otherwise it stays a draft.
Publishing again needs the step two fields
Publish stays inactive until a title, a thumbnail, a publication type and at least one discipline all exist on the publication. A missing PDF is the exception: it leaves the button active and is refused when you press it, so check the file is really there. Something that was live already carries all five, so this normally passes without any work. If it does not, why the Publish or Next button is greyed out lists what each editor is waiting for.
If the Drafts tab looks empty
The number beside Drafts is counted on our side across every draft on the account, not only the cards loaded on screen, so treat it as the reliable figure. If it reads zero, the draft is not on this account, and the next thing to check is which member you are signed in as.