The cluster points at a page that is closed from indexing. The link is there, the destination cannot be used, and the cluster is weaker for it.
The finding reads:
warning hreflang-target-blocked the alternate … is closed to indexing, or its canonical points elsewhere — the cluster points at something that will not be in the index
Open the alternate page for indexing or drop it from the cluster: a blocked target weakens the whole cluster.
Collapsed when it fires template-wide. If it appears on 90% or more of the pages — or of one language version — of a site with at least 20 pages, it is a property of the template and is reported once, with the count, instead of once per page.
pipx install indexgap
cd your-project
indexgap init
indexgap check
Then indexgap brief turns
every finding on this page into a work order in indexgap-briefs/,
with the thresholds the result has to satisfy and the command to check it.