Recovering a Lost Sitemap: Tips for Restoration and Backup

Hey guys 🫠 - I just finished a somewhat bigger sitemap on my project, and was ready to export it - just wanted to allign 2 sections differently and now half of my pages vanished! I can't hit undo - "There is nothing to undo". I tried duplicating it - but no luck. It's all gone 😞 What do I do? Is there a snapshot on the system somewhere? Or do I really have to do it all over again? I customized every section and wrote whole copy briefs in there ... Is there a chance to get it back somehow?