iMessage app not opening & can’t restart phone

Hi,

my imessage app won’t open and I can’t restart my phone (volume+ button and power). When I try to restart it, the “swipe to turn off” screen only appears twenty minutes later. I can soft reset (which I have done multiple times in the past week) and it temporarily lets me use imessage but soon later it goes back to a blank black screen when I open the app and after a dozen seconds, it just closes. I can’t restart the app either because the imessage settings either won’t open either. (Something similar happened with the cellular data settings a few weeks ago. I couldn’t open the settings for it.) I suspect it’s all the same problem because the not powering off issue has been going on for two weeks.

This issue is with new month old iphone 14 and up to date ios. Storage is halfway filled.