- Check your internet connection. Make sure that your iPhone is connected to a Wi-Fi network or has a strong cellular signal. If you're not sure, try opening a website or app that requires an internet connection.
- Free up some storage space. The iOS 16 update requires at least 10GB of free space. If you don't have enough space, you'll need to delete some apps, photos, or other files.
- Restart your iPhone. Sometimes a simple restart can fix software issues. Press and hold the power button and the volume down button at the same time until you see the Apple logo appear.
- Update your iPhone using iTunes. If you're still having trouble, you can try updating your iPhone using iTunes. Connect your iPhone to your computer and open iTunes. Click on the "iPhone" icon in the top left corner of the window. Then, click on the "Summary" tab and click on the "Check for Update" button. If an update is available, iTunes will download and install it for you.
If you've tried all of these things and your iPhone is still not verifying the software update, you can contact Apple Support for help.
Update your iPhone, iPad, or iPod touch with iTunes - Apple Support
I hope this helps!