How to tell who is servicing your electricity?

Looking for a way to search which company is servicing electricity. I have a vacant rental property that I am in the middle of flipping in the 77091 zip code and I was informed that a new company is servicing my electricity but I do not know who it is.

I have had a Reliant month-to-month plan on it for the past six months. Yesterday I received an email from Reliant saying they are "sad to see me go" and they would have my final bill prepared within a week. Confused, I called them and was informed that another electric company had taken over my electricity contract. However, I did not consent or authorize this. Reliant asked me if I had spoken to anyone at the grocery store or to someone who knocked on my door but I have not. And I live about two hours away from Houston anyway. I do not receive mail at the property in Houston. I am trying to figure out a way to see which company is now servicing the electricity on the property as I am concerned there has been a mistake (or fraud). Thank you in advance for your help.