I am unable to download the update iOS15.7.1! It keeps giving me an error message! Any ideas!

You should have listed the exact error message in your post so that the readers of your post understand what you are seeing on the screen when attempting to update your iPhone.

Make sure that your iPhone is setup to meet the following requirements before you attempt to update the iOS version over a Wi-Fi Network. Open Settings ➡️ General ➡️ Software Update: If there is an update available for your iPhone then it will be listed here. Follow the on-screen instructions to download and update your iPhone. 

• Your iPhone must have a fast Wi-Fi connection; you cannot update over cellular data or a cellular hotspot
• The iPhone can not be in Low Power mode
• The battery state of charge must be above 50%
• Your iPhone must have at least 6GB or more free storage space
• Your iPhone cannot be connected through VPN
• You should leave the phone plugged in until it finishes updating, both to assure that it remains above 50% and to keep Wi-Fi enabled (Wi-Fi turns off when the phone sleeps if not connected to power).

Axel F.

Mgthigs1 Said:

"I am unable to download the update iOS15.7.1! It keeps giving me an error message! Any ideas!: I am unable to download the iOS15.7.1 update on my iPhone 12 Pro. I repeatedly keep getting an error message! Any thoughts?"

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Updating an iPhone 6s Plus:

A. Update Using a Computer:

Cancel the update, and then plug it into a computer, and then install this update through a computer.

• Use my User Tip:  Update your iPhone Using a Computer - User Tip
• IMPORTANT: If you have an option to update, however, then be certain you backup your iPhone first. That way, you will have something to restore your iPhone from should anything go wrong with the update.

B. You Must Update Yourself:

No one here can update your iPhone. These are just user-to-user forums. No on here has any access to your device (and that is a good thing, BTW).