My iPhone XR just locked up completely. It is stuck on shut off screen - but touch commands do not work. Phone function works. I inadvertently dialed 911 with volume/shut off side buttons. I just installed 14.4.2 yesterday. How do I turn it off, or g

The iPhone XR has a different way of forced restarting than what you tried.

To forced restart. First take off any case. Then:

Press and very quickly release the volume up button. > Immediately press and very quickly release by the volume down button > Immediately press and hold down the side button and keep holding the side button until the Apple logo appears, release the side button.

JCC46 wrote:

Same thing--SE just randomly shut off with 82% power; this had happened several times shortly after I bought the phone last summer. I fairly recently installed an update; is it related to running 14.4.2? Yes, I can restart it, but why should I have to? The phone is less than a year old.

Well, it’s called an iPhone, but its actually a very powerful pocket-sized computer that runs Unix that can also make phone calls. And like all computers it will crash occasionally. One way to make it less likely to happen at an inconvenient time is to restart it periodically, for example, once a week→Restart your iPhone - Apple Support

Apple SE is locked this morning after overnight automatic update to IOS 14.4.2. After entering passcode it won't let me out of the three update notification screens. Rebooted phone to no avail. I can receive calls but have no control of my phone beyond on/off and answering incoming call.

My ipone is locked and I can't power off or use the phone

Read the Apple Recommended post, above.

Same thing--SE just randomly shut off with 82% power; this had happened several times shortly after I bought the phone last summer. I fairly recently installed an update; is it related to running 14.4.2? Yes, I can restart it, but why should I have to? The phone is less than a year old.