I’m unable to install iOS 15.6.1 on my iPhone 11 Pro max after downloading it

I am having this problem on iPhone SE. I get a generic “Unable to install update - An error occurred installing iOS 15.6.1” message. My battery is 100%, plugged in , and not in low power mode. I have tried a dozen times with no success.

No add-on VPN client app loaded, and no iOS beta profile loaded, and connected on Wi-Fi?

Delete the download, and re-download? Settings > General > iPhone Storage > find the update and delete it.

What happens when you try?

Is your phone battery over 50% charged or connected to a charger?

Do you have low power mode turned off?