Somes boxes disappear

I created a new page and a added several boxes with a lot of content (article boxes)

I noticed that I have to flush caches many times to see my boxes
This page wasn't published

I decided to copy this page and 4 boxes desappeared on the copy and the original page. No way to display the missing boxes (I try to flush caches on jahia and on my browser)

Publishing doesn't resolve the issue

this boxes had content only in one language in a multilanguage site

No exception on the logs