Can't see the iOS 8.4 update in my iPhone 6 plus
I'm using iOS 8.1.3 on iPhone 6 plus and I can't see the iOS 8.4 update on my phone. It sees iOS 8.3 update instead. I've never done jailbrake or anything similar to that. What should I do?
iPhone 6 Plus, iOS 8.1.3, 64 GB