i am unable to update my iphone due to low space

VPN or proxy connections might prevent your device from contacting the update servers.

• If everything fails:- Use iTunes or Finder (for macOS Catalina+) to update your device instead of over-the-air

• Get help with iOS update and restore errors - Apple Support
• If you see an error when you update or restore your iPhone, iPad

You will need to delete something to get more space or try updating through iTunes on your computer.

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