ORAS works on a time based cycle. If you mess around with the clock, it will take 24 hours to reset back to the usual programmed gameplay. This could affect things like flags, berries, legendary Pokemon, etc.. Uxie's time is 8pm-9pm on any day of the week. If you messed around with the time, wait 24 hours and then wait until the time they arrive. It will normally take about 2 days to reset.
This is because you went ahead of the gameplay. Therefore, the usual things you collect daily will be pushed back 24 hours from where you time cheated. It might work on the first time, but don't depend on it. It's terrible!
Hope I helped! :)