Hi ​@Louise Urquhart, thank you for reaching out! To help investigate further, could you share a screen recording of what’s happening? That’ll help me try to reproduce it on my end.

A few questions to narrow this down:

• Is this happening in the desktop app, the browser, or both?
• Does this occur with a specific file or across all files?
• Have you tried clearing the cache to see if that resolves the issue?

Let me know if you have any additional details to share, thank you! 

Happens to me occasionally when I’m not careful. My explanation was that I accidentally selected flatten in the context menu, or pressed Ctrl + E. I’ve catched myself doing it a few times.