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What device do you have?
When you say that you altered the schedule, did you change the schedule you were using previously or create a new schedule?
How are you creating these schedules? Directly in the DND settings, through Bixby, if you have a Samsung, or some other way?
Have you verified that all components of the new schedule are correct?
This time that it failed, did you simply wait for the time that it was supposed to take effect and then notice that it was off before the set time? Have you tried setting up a fake/test schedule to see if it followed that schedule? This might let you know if there is a problem and perhaps shed some light on what is or isn't happening.
What is the trigger for the schedule? Time, location, both?
I would set up a new schedule and verify if it working or not. In the meantime if you would like to reply to this thread and receive notifications when others leave replies, please create an account. This link will help you do that..
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