My Prius died in the middle of the highway today!

It is at the Pep Boys for now and I wanted to get “second opinions” on what went wrong, if possible?

Car started perfectly normally, was driving as usual. Had lunch, bought some groceries and was on the way home on a fairly busy highway near my home. Red light ahead, everybody slowing down including me. Car paused…then light turned green. Everybody started moving again but when I hit the gas, my car didn’t budge!?!

I turned my car off totally, waited a minute or so, and restarted. it seemed like every light on the dashboard was on…literally lights I have never seen before. I tried to put the car into Drive but it would only go into Neutral. However I still had music playing, had air-conditioning, could roll my windows down and up as usual?

Stuck in the center lane of the highway! So I called 911, cops came and pushed me to the side of the road (thank you guys!!!) and tow truck came and towed it to Pep Boys - the only place open on Saturday.

They have replaced the 12volt battery, but that did not,fix the issue. Their “master tchnician” is going to look at it on Monday morning, but I want to be educated and not just believe everything they tell me (and charge me for…)???

if this has happened to you, what did it turn out to be?
Or any ideas….?
Thanks!!!