Dear maintainer,
I see that the package eliom (version 11.1.1-2+b9) recommends libeliom-ocaml-doc
which is not in unstable.
This can be seen in https://packages.debian.org/unstable/eliom
In the eliom debian/changelog I read:
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eliom (10.2.0-1) unstable; urgency=medium
* New upstream release
- use ocaml_dune dh build system
- building doc is broken upstream; drop libeliom-ocaml-doc altogether