# March 26, 2026 - New REST endpoint for reconciling the opposite child additions of a linked series

**URL:** <https://community.cumulocity.com/t/march-26-2026-new-rest-endpoint-for-reconciling-the-opposite-child-additions-of-a-linked-series/14418>\
**Category:** Application Enablement\
**Tags:** app-enablement, Feature, digital-twin-manager\
**Created:** [March 27, 2026, 7:27am UTC](https://community.cumulocity.com/t/march-26-2026-new-rest-endpoint-for-reconciling-the-opposite-child-additions-of-a-linked-series/14418 "2026-03-27T07:27:58Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![cumulocity](https://dub1.discourse-cdn.com/flex005/user_avatar/community.cumulocity.com/cumulocity/32/31990_2.png) [@cumulocity](https://community.cumulocity.com/u/cumulocity)\
**Post date:** [March 27, 2026, 7:27am UTC](https://community.cumulocity.com/t/march-26-2026-new-rest-endpoint-for-reconciling-the-opposite-child-additions-of-a-linked-series/14418/1 "2026-03-27T07:27:58Z")

</div>

## Context

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**Change Type:** Feature  
**Product area:** Application enablement & solutions  
**Component:** Digital Twin Manager  
**Deployed at:** [eu.latest.cumulocity.com](http://eu.latest.cumulocity.com), [apj.cumulocity.com](http://apj.cumulocity.com), [jp.cumulocity.com](http://jp.cumulocity.com), [cumulocity.com](http://cumulocity.com), [us.cumulocity.com](http://us.cumulocity.com)

> **Technical details**
>
> **Build artifact:** dtm (1024.4.0)

## Description

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When an asset links to a measurement source on a device, the platform maintains a reverse index (`c8y_LinkedSeriesReverseIndex`) on the device that tracks which assets reference it. Previously, if this index became out of sync with the asset-side configuration, there was no dedicated API endpoint to correct it.

The Digital Twin Manager REST API now includes a new endpoint to reconcile the opposite `ChildAddition` of a `LinkedSeries` (also known as `MeasurementSourceLink`): `PUT /assets/{assetId}/linkedSeries/{fragment}/{series}/opposite`. The endpoint updates the `c8y_LinkedSeriesReverseIndex` managed object on the device side to accurately reflect the asset-side source reference. The optional query parameter `removeMissingSourceId` removes the `source.id` if the linked device no longer exists. If the device is not found and the parameter is not set, the endpoint returns a 422 error.

Developers and administrators can use this endpoint to programmatically correct synchronization issues in linked data point configurations without manual intervention.