Someone once asked...
Someone answered with kindness...
Throw it in a lake and walk away!
Another soul answered...
Really? Of all the things?
Another soul answered...
Try making the screen grey scale. Also put the charger far away from your bed. Temporary blocking apps like Forestry are also nice, start with small times (ten minutes, twenty minutes) and slowly work your way up. Most importantly... find something else to occupy your time that feels more substantial. What do you do on your phone? Doomscrolling social media? Addictions are most of the time less about the stuff that's addicting but about the fact that it fills some hole. In theory you could be on your phone all the time and feel great about it because what you do on there is vitally imporant and spiritually fulfilling (IDK like that BeMyEyes app where blind people take pictures and you describe whats in it for them). So think not about the phone but what you actually want to do instead and why you're not doing that.
Another soul answered...
Making a dumbphone from my smartphone actually helped me, I deleted all social media apps and messengers, only work stuff left. The screen time dropped from 1.5h to 45m in 3 weeks(because I need to call my mama and relatives) The most important thing is reality-illusions check. Do you actually want to decrease time in phone? If yes - you need to take time and place to think about it - what actually you want and how you will do it. (THIS IS THE MOST HARD PART) because when you now what and how - it's easy.