I feel your pain, and dealt with similar feelings when I worked a job that I didn't find satisfying or challenging.

There are plenty of ways to turn the downtime at a boring job into an opportunity to learn something useful or find time for self improvement. Something like jotting down notes about a project you want to start or topic you want to learn more about can get you away from the phone, even if it's only for a few moments.

I found it easy to break the doom scrolling habit by replacing it with reading books instead of garbage on the internet. I downloaded an e-reader app for my phone at first and used a free library membership to find some authors and topics to get me started. In my case I eventually got annoyed by the notifications and phone nonsense while I was trying to read and switched to a dedicated e-reader. YMMV.