IPhone 5 doesn't notify me about anything?

I've had my iPhone 5 for almost a year now and about a few months ago, my phone stopped notifying me of texts, calls, alerts, etc. When i wake my phone up I can see the notification, but it never rings. For example my phone doesn't ring until the person calls me twice. Texts don't ring at all and neither does any other app.
Things I've tried:
- Turning the ring ON
- changing sim cards twice
- looking at the settings

I know you have looked at the Settings but just in case your aren't looking at the right place, try this:
Settings
Notification Center

Keep all the things you want on, turned on. Make sure the apps you want on are on as well.

Check if do not disturb is on.