Electric bill went up without using it?

Okay so last month our electric bill was $75. The only thing in our house that we pay electric for it lights and heating and stuff.

We’ve been on vacation for the last month. Heat was off, lights off, unplugged everything, and now they sent us the bill saying this months is $150! That seems crazy. We were literally home for one day this month. We don’t have TVs in our house, or a washer and dryer. We don’t pay for water. All we did while we were home that one day was turn on some lights, clean and leave. I’m so confused 😩 can anyone help understand why its so expensive?