How to update my iPad Air?

The quoted model number corresponds with an iPad Air2. The Air2 is capable of update to iPadOS 15.7.3 - but does not support iPadOS16.

If your iPad is capable of update to a more recent version of iOS/iPadOS than is currently installed, these support pages outline both the available methods by which the update can be performed - and troubleshooting should you experience difficulties:

Update your iPhone, iPad or iPod touch – Apple Support

If you can't update or restore your iPhone, iPad or iPod touch – Apple Support

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

iOS update and restore errors – Apple Support

Be aware that while an iPad may be capable of update, in some circumstances you may need to use a computer to perform the update. To do so, you will need access to either a Window PC (with iTunes for Windows installed) or a Mac (with iTunes or Finder - as appropriate for the installed version of MacOS). Ensure that your installed version of iTunes has been updated to the most recent version; the essential device drivers are included.

Download and use iTunes for Windows – Apple Support

Update to the latest version of iTunes – Apple Support

Update software on iPhone, iPad or iPod touch in iTunes on PC - Apple Support

If you have a beta profile installed, ensure this has been removed from your iPad - as, otherwise, installation of production software updates may be inhibited. This support page provides the necessary information to remove the beta from your iPad:

How to uninstall iOS beta software - Apple Support

You should note that for your iPad to install an available update, its battery must be charged to at least 50% capacity - and/or be connected to its Power Adapter. Similarly, the iPad can only be updated over a standard WiFi connection - or be updated by a PC or Mac using iTunes or Finder - over a USB connection.

Presumably your iPad indicates that iPadOS 15.7.3 is installed? Check here:

Settings > General > About

If iPadOS 15.7.3 is installed - and you are still being prompted to update to iPadOS 15.7.3, perhaps you currently have a beta-version installed. If a beta profile is present, installation of production software updates may be inhibited. This support page provides the necessary information to remove the beta from your iPad:

How to uninstall iOS beta software - Apple Support

Otherwise, performing a forced-restart of your iPad may clear the issue:

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

swwber wrote:

Sorry that should say 15.7.3 is downloaded

If the iPadOS 15.7.3 update has downloaded and failed to install, the update package may have been corrupted. If you are unable to proceed with the update, you’ll need to delete the failed update from your iPad.

From iPad settings:

Settings > General > iPad Storage

Scroll down the list of Apps until you find the update package; swipe to the left, then tap Delete.

Having deleted the update package from your iPad, perform a forced restart:

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

After restarting the iPad, return to the update page - and attempt to install iPadOS 15.7.3

15 I beleive.