mueslee Sorry, sometimes we just miss threads despite our best efforts.
I'm not able to replicate your issue on my Quest 2 or on the main site. Is it on your device that you're having this issue, and if so which one? Or on the website?
The first thing to double-check (and I'm sorry for point one out that's so obvious) would be that you're looking at the correct playlist, as it's possible the playlist menu may default to a different playlist than you have actually been adding scenes to.
The second question would be how many items are already in your specific playlist? Just to confirm it's not an issue of the "page limit" limitation.
Aside from that I'd also suggest trying the standard "delete your cookies/cache" and relaunching the app/site.