Try resetting that app by clearing data then force stop it .Yeah, just messages. Im using the stock messaging app.
It was working fine until my phone updated, so I'm afraid that it may have removed that feature or something?
Can I show me a screenshot of your lock screen setup in settings?I finally know how to explain exactly what I want it to do lol.
I want the lock screen to light up when I get a text message, but I don't want the icons on there, and I want it to only light up with text messages. This is how it was working before the update. Also, when I shake my phone it doesn't vibrate when I have an unread text message.