Hello cqskie,
You mentioned that automatic updates are turned off; just to confirm, did you verify that by going to Settings > General > Software Update > Automatic Updates, on your device? We just want to make sure the settings are configured correctly, so we can make sure there's no issue there.
This link has more information about how to manage automatic update settings, and may be helpful: Update iOS on iPhone
Update iPhone automatically
If you didn’t turn on automatic updates when you first set up your iPhone, do the following:
1. Go to Settings > General > Software Update > Automatic Updates.
2. Turn on Download iOS Updates and Install iOS Updates.
3. When an update is available, iPhone downloads and installs the update overnight while charging and connected to Wi-Fi. You’re notified before an update is installed.
If Automatic Updates are turned off successfully and you continue to experience an issue, please contact Apple Support for assistance. You may be able to reach them here: Contact Apple Support
Thanks!