This appears to be a problem that affects iOS 9 and iOS8 (maybe more) since iOS 9 was released... Ask Siri for the email address of a contact. Try ones that you are related to (e.g., "What is my wife's email address?"). In a lot of cases, Siri will respond that there's a problem. Now ask Siri for the contact information for that person (e.g., "What's my wife's contact information?"). She'll correctly bring up the entire contact card (including that email address). Ask her for that person's phone number and she'll tell you. But she can't tell you the email address. Oddly, she will tell you some email addresses (I haven't found a pattern yet). The problem is compounded when you try to tell Siri to message someone (e.g., "Send my wife a message this is a test"). She'll respond that she can't find any phone numbers or email addresses...but she'll gladly bring up the entire contact sheet for that person (e.g., "Show my wife's contact information"). So she knows the relationship and can find the contact, but then something is lost right before trying to actually send the message. I think it's a problem on Apple's servers. The same exact problem happens on our iOS 8 devices.