Ios 16.2 on iphone 8plus

Emnof ~ Apple's iPhone User Guide says: "If your iPhone isn’t working as expected, you can try restarting it by turning it off, then turning it back on. If turning it off and on doesn’t fix the issue, try forcing it to restart.":

Turn iPhone on or off - Apple Support

..,But if no luck with that, does your iPhone 8 Plus still have its original battery?

And what's the Maximum Capacity % here?...

Settings > Battery > Battery Health & Charging

õ¿õ¬

Emnof ~ To be clearer, this icon is the Settings app:

...Tap it to open Settings app. Then scroll down to Battery and tap it. Then tap Battery Health & Charging and tell us what the Maximum Capacity % is. If its value is only "––", let us know that.

õ¿õ¬

Emnof wrote: "Many thanks. Tried this before with no change. Just tried again and so far at least I managed to get back on this page.

appreciate your time and help"

And, again, does your iPhone 8 Plus still have its original battery?

And what's the Maximum Capacity % here?...

Settings > Battery > Battery Health & Charging

õ¿õ¬

If you have any security apps or VPN remove them and their profike and try again

You has an internet connection problem which has now cleared up.