EventConsole CS0246 error

I am using VS2019 and building out dialog boxes for my app. I am playing with the demo code and am able to get the RadzenCards to work but when I attempt to open as a dialog I am getting the EventConsole CS0246 error.

I have added all the Radzen lines listed in the Installation Guide. As well as inject JSRuntime.

Fixed.. I read that a thousand times. Still took 20 minutes for me to figure out to modify the _Host and create a shared page.

Although this is a stupid question, can I ask you what exactly this means? What code does it correspond to?