Raymarine RL70CRC GPSRadar
There is a feature in these chartplotters called "Plotter Mode" that is often misunderstood and causes the exact problem you describe.
Press menu.....chart setup.....and scroll to the bottom until you see Plotter Mode in the list of options. It should be set in the OFF position.
If you have more than one display networked onboard check the setting in each one invividually.
What Plotter Mode does is allows the chartplotter system to access range scales not supported on the chart. It is not normally used for map-based navigation but more so for chartless electronic plotting (it can display routes, waypoints and track-recorder breadcrumbs.) open-ocean cruising, or for ultra-precise GPS operations (like a precision anchor drop, finding a very specific location etc. When plotter mode is on you can zoom in to a very, very small working area. The indicator it is enable is the cross-hatch background on the screen, the lack of map information, and the NO CHART DATA watermark on the screen.