Error Code 49-430

I retired as an installer 12 years ago, but still do occasional trouble shooting work for friends. I have a friend who built a tiny home for his father adjacent to his home.  His father previously lived in a trailer on the same property.  They operated with separate antennas, both using SWM, friend using an HR-24 and father an H-44/500.  I wired the tiny home using a splitter out of the IRD port on the  power inserter, one splitter output going to the HR-24 and the other to the tiny home.  There is an additional splitter in the tiny home, with coax going to 2 locations, only 1 of which is used (by the H-44).  I'm getting a picture with an error message superimposed over the top saying there are too many receivers connected.  Can someone help?