Motorola Moto G 4G — Android Reinstall

I have a Motorola G phone. It was being used by one of my employees and he said he was doing a system update and now the phone is in a continuous loop of restarting. It restarts then the android comes up and it says erasing and after 5 seconds restarts again and does this over and over. It will not go into recovery mode or anything at all. I spoke with the folks at Motorola and they are telling me the factory software has been modified or altered or something on the phone and are basically refusing to help. I have no idea what this means. I just want to know how to reinstall the OS on it so it can work again.

Sorry in advance if this Is posted incorrectly or in the wrong place.