iOS9 iMessage issues.
I have an iPhone 6, and just a day or so ago updated my phone to iOS9, to the most recent. I believe it's the second update for iOS9. My iMessage with some people will not say delierved, but I know they got the message because they respond to what I said. I have restarted my phone and restarted network settings.
iPhone 6, iOS 9.0.2, I am with Verizon.