Please whenever I wanna update my phone to iOS 12.5.6 it isn’t working,the place which says download and install isn’t appearing properly it’s faint

As shown in your screenshot: you must connect to a Wifi network.

Also charge the battery and preferably leave it connected to the charge circuit during the update process.

Also turn off the Low Power Mode option.

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).

• Are not using a VPN connection.

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

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

Minarshe Said:

"Please whenever I wanna update my phone to iOS 12.5.6 it isn’t working,the place which says download and install isn’t appearing properly it’s faint"

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For reference...

Updating an iPhone:

Determining if an Update will Install:

How to do so...

A. Verify Compatibility:

Identify your iPhone model. The first thing that comes to mind in incompatibility being the culprit. So, confirm the model of your iPhone. If iPhone model is incompatible with iOS 16 then it is because you iPhone does not meet the hardware requirements for this iOS version(s).

B. If Compatible...

1. Back Up First:

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

then...

2. Proceed with the Update:

Use my User Tip:  Update your iPhone Using a Computer - User Tip