Has anyone successfully kept weight off after a fast?

At the end of 2023, I did a 21 day water fast and went from 240lbs down to 220lbs. I swore I was going to eat healthy and stick to natural foods afterwards but quickly went down the slippery slope of back to my favorite foods. Well, fast forward a year later and I'm now at 270lbs. I'm considering another extended fast but afraid that I'm going to end up at 300lbs when I break my fast. Advice?