Sometimes we have minor issues with the exact representation of Elements and their position that could cause some hidden elements. So, when this is happening it's the best practice to try to introduce a small gap in the location, just some tiny number different from zero can solve it because normally it is due to some misalignment in the three-dimensional representation of the models.
It could happen with Substructure and Accessory: If they're Bearings, the solution could be to slightly move the Support lines, or with a Barrier, it could be to introduce a Horizontal offset directly.
To check the creation of Elements it is important to verify at the Explorer Window in the OpenBridge Model all the elements inside their respective Units in the Bridge model.