[ORAS] How do I catch Uxie?

[Siqueirapowered]

Why can I not battle Uxie? I'm at Nameless Cavern and when I interact with the portal nothing happens. I've set my time to be between 20:00 and 21:00 already

[IceyGamer]

By changing your time on your 3DS events will not occur until 24 hours after you adjusted it. Then you wait it out until live time on your 3DS is between 20 and 21.