ElasticSearch Issue regarding ConfigService.php line 124

Please don’t annotate the following would be an ElasticSearch issue. The guys in discuss.elastic.co insist this should be an NextCloud issue.

I’ve tried to index my NextCloud for the first time. But I’ve been getting an error message:

pi@raspberrypi:/var/www/html $ sudo -u www-data php /var/www/html/occ fulltextsearch:index

In ConfigService.php line 124:

Your ElasticSearchPlatform is not configured properly

fulltextsearch:index [–output [OUTPUT]] [-r|–no-readline] [–] []

pi@raspberrypi:/ $ sudo find -name ConfigService.php
./var/www/html/data/updater-ocaq47xct6b3/backups/nextcloud-16.0.1.1/apps/fulltextsearch_elasticsearch/lib/Service/ConfigService.php
./var/www/html/data/updater-ocaq47xct6b3/backups/nextcloud-16.0.1.1/apps/fulltextsearch/lib/Service/ConfigService.php
./var/www/html/data/updater-ocaq47xct6b3/backups/nextcloud-16.0.1.1/apps/files_fulltextsearch/lib/Service/ConfigService.php
./var/www/html/data/updater-ocaq47xct6b3/backups/nextcloud-16.0.1.1/apps/gallery/lib/Service/ConfigService.php
./var/www/html/data/updater-ocaq47xct6b3/backups/nextcloud-16.0.0.9/apps/gallery/lib/Service/ConfigService.php
./var/www/html/apps/fulltextsearch_elasticsearch/lib/Service/ConfigService.php
./var/www/html/apps/fulltextsearch/lib/Service/ConfigService.php
./var/www/html/apps/files_fulltextsearch/lib/Service/ConfigService.php
./var/www/html/apps/gallery/lib/Service/ConfigService.php

Which of these files is the proper ConfigService.php, within I have to fix line 124?