Having glitch in the brightness and volume bar of my iPhone

iOS updates generally aim to enhance user experience, boost security, and fix bugs rather than disrupt core features. Volume and Brightenss 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.

This seems purely coincidental so please check the Setting on your device. If a button or switch isn't working - Apple Support (IN)

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...

You may try some of these steps, please check after each step...

1. 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
2. Some users have reported that disabling "Reduce Motion" in Settings > Accessibility > Motion can help with certain display-related glitches.
3. 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.

You may get better and prompt responses if you may kindly provide the iPhone Model that you have and the iOS version if it is known to you and re-post.

With the limited information that you have provided, It is hard to even guess the problems faced by you. 

You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.

I have the same issue on my iPhone 14 and on my 9th gen iPad. Turning off auto brightness fixed it, but adjusting your brightness manually every time is really inconvenient. Still happening with the volume bar though.

I have updated my ios to 17.4 and the problem with volume started 2 days ago. I struggle to lower it down, but it automatically increases to the maximum. Now I can't even watch music or videos, because I can't seem to lower the volume. It keeps flickering on my screen, pops up and disappears the entire day. I am so frustrated. I even tried updating my IOS to 17.5, I reset of settings, restarted, and tried all setting solutions people posted online, but NOTHING worked. Is there someone who has found a FIX for this issue. It's driving me bananas.