Major cause of insomnia?

Major causes of insomnia are

1. Stress
2. Anxiety
3. Depression
4. Poor sleep habits
5. Excessive screen time before bed
6. Irregular sleep schedule
7. Caffeine or stimulant use
8. Medical conditions (pain, asthma, reflux, etc.)
9. Medications
10. Noisy or uncomfortable sleep environment
11. Lack of physical activity
12. Hormonal changes