My teenage daughter was taking 45 minute showers. I’d yell and scream at her that she was wasting water. I’d lecture that her showers were too long but nothing deterred her.
Finally, I decided to replace action with threats and said “Sweetie, you get 15 minutes to shower and then I’m turning off the hot water.”
It worked! She started taking 15 minute showers. All those months of lectures and warnings and all I needed to do was take action. Amazing!