This issue is not reproducible.
The ServerGen updates after every edit is made to the underlying database. Make sure the newly updated serverGen is supplied after an edit is made.
Try reviewing this article: https://support.esri.com/en-us/knowledge-base/extracting-changes-from-the-change-tracking-table-000025224.
As well as the ArcGIS REST APIs documentation examples here: https://developers.arcgis.com/rest/services-reference/enterprise/extract-changes-feature-service/.