I noticed this on my 6S and now on my 7 Plus so I know it's a software issue. Certain notifications don't open on tapping anymore. Snapchat, instgram sometimes, and facebook messanger. Maybe more. If I just tap on them.. nothing happens.. if I force touch it and then tap on it.. it'll open just fine. Please tell me I'm not the only one experiencing this because it makes me wanna pull my hair out.