Line break missing in asciidoc

[matiya]

My pandoc version

pandoc 2.9.2
Compiled with pandoc-types 1.20, texmath 0.12.0.1, skylighting 0.8.3.2

I try to convert this org-mode block:

* Header
#+begin_tip
I'm a tip
#+end_tip

** Subheader

with this pandoc command
pandoc -s input.org --wrap=preserve -t asciidoc -o output.adoc

And I get this:

== Header

[TIP]
====
I'm a tip
======= Subheader
   ^

There should be a line break at the caret symbol, but there isn't.