I want to update my iOS version to iOS 15.7.7

Update your iPhone, iPad, or iPod touch

• If you have an iPhone 5S or 6/6plus, the highest you can update to is 12.5.7

• If you have an iPhone 6S through 7, or SE 1st generation, you can update to 15.7.7

• If you have an iPhone 8 or higher, or SE 2nd or 3rd generation, you can update to 16.5.1

Go to Settings > General > Software Update.

This link will show you how to update your iPhone, iPad, or iPod touch using WiFi -

Update your iPhone or iPad - Apple Support

This link will show you how to update using your computer -

Update iOS on iPhone - Apple Support

Click on this link on what to do if you can't update your phone -

If your iPhone or iPad won't update – Apple Support (UK)

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