Map details are very generic and coastline definitions is missing

[Yano67]

Map details are missing and coastal features are missing. Fishing charts don’t have contours of sea bed

 

[Yano67]

This is and example of the display

 

[jp498]

Maybe charts are not installed or active?
Otherwise, consider that charts have improved a bit in the past 20 years.

 

[Johnny Electron]

Make sure you have the chart loaded, selected, and range in and out because it changes based on range. The NN3D units while getting a bit old they normally had the free fishing chart loaded. The free fishing charts when loaded do have areas where it has no bathy. If you are in one of those areas then the $100 C-map bathy map purchase might be needed to provide what you are seeking. It would be best to contact tech support with your system ID and we can see what has been licenced against that system.