We have an existing issue we have logged regarding duplicate line errors for connectivity when the asset group and asset type do not match and there are no supporting rules. This is only going to be reproducible for Utility Network Version 3 and older. With ArcGIS Pro 2.6, utility networks will be created and upgraded to Utility Network Version 4. Utility Network Version 4 started using a new error model where the network features themselves are flagged as errors and there are no longer point, line, and polygon error features.
Both errors are cleaned up after you fix the error situation and validate I assume?
Do you only experience duplicate error features for certain types of errors?