Utility Network diagram is not updated the same as the map view

Description

The ArcGIS Utility Network diagram is not updating after making modifications or edits to the network. This issue is likely related to a synchronization problem between the network edits and the diagram generation process. When the network topology is updated but the diagram is not refreshed accordingly, it may result in outdated or missing diagram elements

Note:
To edit a Utility Network, an ArcGIS Advanced Editing license is required in Portal for ArcGIS.

Cause

Here are some possible causes of this issue:

• Modification is not applied to the diagram
• Update tool from network diagram must run.
• Validation of the network topology not done before updating the diagram.

Solution or Workaround

If the ArcGIS Utility Network diagram isn't updating after modifying or editing the network, here are some steps to take to troubleshoot the issue:

1. In Map view, select the features and generate the network diagram.
2. Modify or Edit the network data as per requirement. Save the edits.
3. Remove the dirty area by validating the topology. 
4. Click to Apply to diagram and select the diagram so that modifications are applied.

5. On Network Diagram tab, navigate to modify and Update the diagram. You can use Append to add set of network features in the active diagram.

This updates the network diagram in regard to the modifications done.