Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
Looking into some info on this here the only way this could occur is if the start/stop/power button was not fully pressed to turn off the engine when this occurred and it was in gear or it is slightly possibly the on/off/power button has shorted out causing the engine to start but this wont put the vehicle in gear at all.
Ive looked through many resources on this here,the button itself can be an issue but this wouldnt explain being in gear so having this occur all together like this seems impossible unless it was still in gear and wasnt shut off properly.
The best thing to do here is to have the codes checked to see what codes are set.This has to be done using a scan tool that will plug in and communicate with all computers.If there are any codes set related to the stop/start feature there is a possibility the button or possibly even computer is at fault but this is a long shot unfortunately.
In most cases I see where this occurred it was user error I hate to say when the vehicle was still in gear and vehicle was not shut off properly.I know some of these models had a remote start system installed that can cause the vehicle to start on its own when it acts up needing replaced but this wont cause it to engage in gear to go down the road or in neutral.
I would start with having codes checked and the signal from the start/stop button checked into as well as remote start if equipped as these would be the only things that could possibly cause this here.I know this may not be the answer you wanted to hear but it's the only thing that makes sense with what occurred.
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