My iPhone is stuck on preparing update but won’t update

Preparing to update can take a while. 30 minutes would not be unusual, and it also needs to meet a list of requirements. To update over the air from the phone all of these requirements must be met:

• To update over the air from the phone all of these requirements must be met:
• You need at least 10 GB of free storage for iOS 16 and later or 6 GB for iOS 15 or lower; more is better
• You must be connected to a Wi-Fi network (and not a personal hotspot)
• The phone must be charged to at least 50%, and preferably plugged in so it stays above 50% during the update
• The phone must not be in Low Power Mode
• The phone must not be connected through VPN, and it may be necessary to delete any VPN apps and VPN profiles
• The phone cannot be in Airplane mode and must have a cellular data connection
• You cannot still have a beta of a previous version installed on the phone
• You cannot have a previous version that was downloaded, but not installed - go to Settings/General/iPhone Storage to look; if you find an iOS installer, delete it

If you can't meet all of them you can still update using your computer.