On Wed, Apr 12, 2023 at 08:03:28AM -0400, Tom Lane wrote:
> In any case the path to follow is to manually fix the duplicates
> and REINDEX.
A latent bug in Postgres could be a possibility, as well, but it is
not really possible to rule out that without more details.
I don't recall anything specific that's been fixed in 13.10, but you
should update to it, at least.
--
Michael