First, adjust your mental model. You haven't "fixed" your relationship with technology—you've begun a lifelong practice. Think of it like physical fitness. You wouldn't expect 30 days of exercise to keep you fit forever. Digital fitness requires the same ongoing attention.
The key is shifting from a "challenge" mindset to a "practice" mindset. Challenges are intense, time-bound, and focused on dramatic change. Practices are sustainable, ongoing, and focused on gradual refinement. Your 30-day challenge taught you the fundamentals. Now you develop mastery through consistent practice.