How to update my phone
how can I upgrade my iPhone 6 to iOS 12.5.5
iPhone 6, iOS 12
Question marked as
You must have a stable Wi-Fi connection.
Or connect to a PC with the latest version of iTunes installed.
Charge the battery to 50% or higher.
Turn off Battery saving mode.
Don't use a Hotspot.
Don't use VPN.
And make sure you have enough free space.