Wife had that issue once with a car we owned.. Forgot to put it in PARK
I had that issue on motor home several times... EMERGENCY START/Boost got it running all but once. That once the batteries were dead and the Boost did not have enough OOMPH New battery fixed
The other times all but one a battery terminal needed cleaning.. The factory used the wrong type of terminal (Wrong metal) and corrosion was an issue, I fixed (Changed terminals)
The last time it was the other end of the negative cable, Tech put on a new lug there too (I could not reach it properly)
I have a adjustable current battery load tester from Harbor Freight (This is the model with two gauges and a knob)
Very useful for diagnosis, found the problem every time.