I’m having the same issue and it just cropped up today. It’s in our Clients collection. URL is correct: Space Angels Case Study but getting “Page Not Found” error. Our entire client showcase is down, which is bad because we have prospects looking at us right now through paid ads.
One thing I noticed is that in the Search Result Preview in the collection page settings, it shows this URL: https://www.lenker.com/UNDEFINED/space-angels. So something is definitely up. This is urgent for us right now.
Here’s the preview link: Webflow - Lenker B