2018 g310r with 1500 miles died in mid ride, cranks over but no start.

I bought this bike for my grandson last fall with only 1300 miles on it. He is 16 and got his motorcycle permit 2 weeks ago. We we're on our 2nd ride when I looked back after rounding a corner and he was not there. I turned around and found him parked on the side of the road not running. He said it just started slowly down and died. It has a half tank of gas and I can hear the fuel pump pressure up when I turn the key on. It turns over fine but doesn't even try to fire up. He and I had planed to ride all weekend and need less to say he's pretty disappointed. I have owned BMWs for the last 45 years, mostly for their dependability. Does anyone have any suggestions on what could have failed? Since it's out of warranty I dread taking it to a dealer. I usually do all of my maintenance, my current ride is a 2016 R1200R and it's been trouble free. Any help on this would be appreciated.