people offering me better electricity discounts when I have none under my name

Called 5 times wanting to talk about electricity. Told many times to stop calling

A very rude phone operator (sounded like from an o/s call center) claiming to be calling about my electricity provider in NSW - when I told her I didn't have one she challenged me as to how I could not have electricity. That number had called me 4x already today, kept calling me back as I didn't answer the earlier calls.

They called me today but I did not pick up.