my Iphone is still 12.5.5 ios, it’s not updated

Check if your iPhone is compatible with iOS 15.

Identify your iPhone model - Apple Support

iOS 15 and iPadOS 15 are compatible with these devices - Apple Support

If your iPhone is compatible with iOS 15, follow the guidance to update to the latest iOS. Otherwise, the device cannot be updated to iOS 15.

How to update to iOS 15 or iPadOS 15 - Official Apple Support

Links that might be helpful:

iOS 15 - Apple

About iOS 15 Updates - Apple Support

An unit running 12.5.5 isn't capable of 13 or above.

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