Screen shot is not working after os update

1. Make sure you are pressing the buttons correctly. To take a screenshot on an iPhone 12 Pro, you need to press and hold the Volume Up button and the Side button at the same time. If you are not pressing the buttons correctly, the screenshot will not work.
2. If you have AssistiveTouch enabled on your device, it might interfere with the screenshot process. To disable AssistiveTouch, go to Settings > Accessibility > Touch > AssistiveTouch, and toggle it off.
3. Make sure your iPhone is not in Low Power Mode. When your iPhone is in Low Power Mode, some features are disabled, including the ability to take screenshots. To check if your iPhone is in Low Power Mode, go to Settings > Battery. If the Low Power Modetoggle is turned on, turn it off.
4. If you have a screen protector installed, make sure it is compatible with screenshots. Some screen protectors can interfere with the ability to take screenshots.
5. If you are using a third-party app, make sure that app is compatible with screenshots. Not all apps allow you to take screenshots.
6. Sometimes, a simple restart can resolve temporary software glitches. Turn off your iPhone, wait for a few seconds, and then turn it back on.
   1. Restart the device. That's it.
   2. Still not solved --> Force restart iPhone - Apple Support
7. If the issue persists, you can try resetting all settings on your iPhone. This will not erase your data but will reset all personalized settings to their default values. Go to Settings > General > Transfer & Reset > Reset > Reset All Settings and confirm the action. Note that you will need to reconfigure your settings afterward. All settings—including network settings, the keyboard dictionary, the Home screen layout, location settings, privacy settings, and Apple Pay cards—are removed or reset to their defaults. No data or media are deleted.
   1. Reset All Settings: Return iPhone settings to their defaults - Apple Support:- Return iPhone settings to their defaults
   2. You can return settings to their defaults without erasing your content.
   3. If you want to save your settings, back up your iPhone before returning them to their defaults. For example, if you’re trying to solve a problem but returning settings to their defaults doesn’t help, you might want to restore your previous settings from a backup.

If none of the above steps resolve the issue, it is recommended to reach out to Apple Support or visit an authorized service center for further assistance. They can provide specific guidance based on your device model and iOS version.

It's not always the iOS update's fault!  Many things can cause phone problems.  If you tell people you think it's an iOS update, it might make it harder to fix or find a solution for the real issue.

Remember, the right question often leads to the solution!

iOS updates aim to enhance user experience, boost security, and fix bugs rather than disrupt core features. The majority of the issues after updates might stem from underlying, unmentioned factors. Updates won't typically alter personal data but may refine settings or features. Backup before major updates for safety. Review Apple's update details and backup advice for a smooth process.

Kindly consider checking your settings and addressing any device issues before attributing the issue to external factors. This could be a pure coincidence that the iOS update affected the iPhone functions.

Before initiating a standard iOS update, it's advisable to create a backup. Have you completed this step? If yes, proceed with the restoration from the backup.

See what each update does: About iOS 17 Updates, About iOS 16 Updates, About iOS 15 Updates, About iOS 14 Updates, About iOS 13 Updates, About iOS 12 Updates, and so on...