nautilus lifeline

Hey all, Wondering if there's someone here who can help me. I just got a Nautilus GPS unit and am trying to program it with my iPhone X, but when I get to the final stage where I'm supposed to point the phone flashlight at the back of the unit to finalize the programming, it never seems to work...

I am selling a brand new still in the box unit (although it did not come with a battery, I installed one which is said to last 5 years). It is the NEW model, recently updated. It has never been in contact with water, fresh or salt. It was bought as a gift but my family didn't realize I already...