I can’t update my software
I can’t update my ipad software
iPad mini 3, iOS 12
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IOS update? Your iPad mini 3 isn't compatible with an IOS version higher than IOS 12.
See the article(s) below which show device compatibility for each IOS version.
IOS 15 and iPadOS 15 Compatible Devices. *
iOS 14 and iPadOS 14 Compatible Devices. *
iOS 13 and iPadOS are compatible with these devices - Apple Support. *