How do I turn my do not disturb off when locked?

If this is your question:

How do I turn off Do Not Disturb when Locked?

Then the answer is:

Settings > Do Not Disturb > [either]…

• Silence = “Always”
• Do Not Disturb = “off”

I suspect you may not be asking the right question. What is the problem you're having? Are you asking why you're phone doesn't ring when locked? If DND is turned off, it is not the cause of your phone not ringing when locked.

Possible causes include the mute switch on the side being enabled and Settings>Phone>Silence Unknown Callers being set to on.