Unable to install iOS 15.4

What happens when you try?

Can you post a screenshot of the whole screen, it could reveal why you aren't able to update.

Make sure you:

• Are using a WiFi connection (not a hotspot).

• You have an active cell signal (You need both WiFi and cellular service to perform the upgrade).

• Have your battery charged at least 50%. Better yet, keep it plugged in during the update.

• Are not using a VPN connection.

• Do not have power save mode turned on.

• Do not have a beta version installed.

• You have at least 6 gigs of storage available.

You can also check out this article for help -

If your iPhone, iPad or iPod touch won’t update

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

DanielleFoley Said:

"Unable to install iOS 15.4: I have enough space on my iPhone. Why can’t I get iOS 15.4?"

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Why the Error?

You are not getting access to Apple's servers.

So, Update Using a Computer:

For a more reliable connection, try updating using a computer... Use my User Tip:  Update your iPhone Using a Computer - User Tip

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