Humminbird Mega 360 not communicating to helix 12 G3N mega DI

Need some info on why my brand new graph which has been updated to recent updates. Then installed the mega 360. Shows in accessorie test that it ain’t connected. First I thought it was connections which I proved not to be the case. I then hooked up my G3N SI helix and it connected immediately. Any thoughts of why the new helix 12 Mega DI GPS G3N doesn’t see mega 360. Could it be the connector that instructs from mega 360 manual and humminbird online wiring diagram to use adapter from graph to y cable 720108-B. Will be loosing sleep on this situation. Humminbird tech support has no answers.
If you or anyone knows the solution. Greatly appreciated