There's a feedback map for reporting mistakes in the Topographic Basemap:
Topographic Map Feedback - http://www.arcgis.com/home/item.html?id=6365ecd9bd6046d4986159d557e67971
There's also a feedback map for reporting errors with the World Geocoding Service, and since the mistake in the Basemap means there's nothing to find in the Search using the World Geocoding Service, it's probably a good idea to report here as well:
Geocoding Feedback - https://www.arcgis.com/home/item.html?id=b7d30c782d63401894b36a44e62f76a9
I'd recommend adding the discrepancy to both.