Page Content Not Shwing

i create a page with a lot of picture.
and in some point the page content is not showing.
it only show the page title.
but it shows up when i devide the page using page break.
the page content is not missing, only not showing.
any suggestions?

is there any page restriction in wordpress?

the page (both have the same content:
with page break: https://hajime-no-ippo.info/characters-list/
without page break: https://hajime-no-ippo.info/characters-list/boxer/

thx before
(sorry for my bad english)