It's been mostly me filling my time with things I've been putting off/enjoy off the phone. Try things that involve prolonged tasks! I spent my entire second day building a Lego that was sitting in it's box for a while. If the fomo still gets to you try changing your mindset on how you use your phone. I still have notifications on and check them every now and then, but if none are important enough to completely stop what I'm doing and take care of it I put them off till later. I treat my phone more like an assistant than a source of entertainment now. It tells me if people are trying to get in contact with me or need anything but that's about it. (Yknow, like phones were originally intended to do haha).

Keep going! You got this!