How do I turn off the double vibrate when I unlock my S8?

[AC Question]

I just got a new S8. Every time I unlock it, it does a little double vibrate. It's incredibly annoying and I can't figure out how to turn it off.
To clarify, I'm NOT talking about the haptic feedback, I mean like a notification vibrate, except:
1. It's not the notification pattern I have selected in settings.
2. I've tried turning off all notifications for all apps and it still vibrates
3. I've turned off Smart Alert and it still vibrates
4. I've turned off Notification Reminder and it still vibrates

I've asked everyone I know with an S8, and I'm the only one whose phone does this.