• Notifications were disabled for the app or silenced system-wide. See How do I turn notifications on?
• On Android, battery optimization, sleeping apps, or Alarms & reminders being off can delay or drop local reminders. See Why didn’t my Android reminder fire? and How do I allow Alarms & reminders on Android?
• The underlying timer or routine doesn’t apply to today (for example, wrong weekday on a weekly schedule).
• You’re using web only. Reminders will not fire as native pushes.

Open Today, Care, and Timers (if shown) to verify what should have triggered.

Note: As-needed Timers during illness are part of Care sessions on the Care tab. Check there as well.