https://wccftech.com/download-ios-15-2-1-and-ipados-15-2-1-released-with-bug-fixes/

Apple has just released iOS 15.2.1 and iPadOS 15.2.1 updates for iPhone and iPad. These updates are available over the air for download.

In order to download the update right away, make sure you have 50% or more battery life remaining on your iPhone or iPad, then head over to Settings > General > Software Update in order to grab the update.