Regarding the heating/cooling, if you’re home is decently insulated look into supercooling in the summer months. At higher temperatures your heat pump has to work harder to cool down the home. By running cooling overnight when temperatures are lower, it uses less power to the same result.
I cool my home to 68f from 2 am until 8 am on a schedule, and then the heat pump stays off until the indoor temps reach 74f. It’s provided a good amount of energy savings and helped me exceed the quoted power offset on my solar setup.
Generally speaking, idle unpaid accounts like this are either sold by the creditors to a third party debt collector, resetting the clock, or they will sue you for the non-payment to get a judgment or lien, resetting the clock.
The only sure bet is bankruptcy, which will drop off your report after a period of time that varies from state to state in the U.S. (generally from 7 to 10 years). Not sure is this applies outside the U.S.