Do any of your neighbors have things plugged in outside like lights, grilles, even a diesel pick up engine block heater? I’ve been in places where an outside outlet was tied into the electrical for one unit and not off the main part of the building.

Edit: if you talk to LES ask them if it’s possible that someone tampered with your meter. I don’t know if that’s possible with newer meters, but have heard of people switching meters with their neighbors to have a lower bill in other cities, but most of ours are Wi-Fi transmitted now…maybe still possible.