Steps to reproduce the issue

1. create an article with no publish down date => index in SmartSearch is OK
2. add a publish down date in the article => index in SmartSearch is updated with this date
3. remove the publish down date in the article => index in SmartSearch still considers the previous publish down date

Expected result

The article should be indexed with no end date, and it should appear in the search requests.

Actual result

The index still has the previous end date, when this date is in the past, the article is not displayed in the search requests.

System information (as much as possible)

Currently running Joomla 5.3.3 with PHP 8.3.25, but this issue may have appeared before.
In #_finder_links, the publish_end_date contains the previous end date instead of NULL.

Additional comments

Rebuilding the index does not solve, I had to first clear the index (Maintenance > Clear Index) and then launch the indexing.