Calendar alerts are, by default, set to alert you a day before the event occurs. But this can be changed and if you sync multiple calendars, it can get changed. Apparently, this can lead to issues like the calendar alerts not working at all.
While there are multiple narratives to this, we’ll look into fixing calendar alerts the way you usually intended. For starters, this is the theme: I want to set up Calendar alerts the way I want. Thankfully, iOS lets you do that. Here’s how.
How to Set up Calendar Alerts for Events/Birthdays etc on iPhone and iPad
Step #1. Open the Settings app.
Step #2. Scroll down and tap on Calendars.
Step #3. Scroll down. Under Calendars, you should see Default Alert Times. Tap on this.
Step #4. You can now tap on each of the options (Birthdays, Events, All-Day Events) to set a specific alert time for these.
Typical Alert Times
#1: For Birthdays, you’d typically want a 1 day before (9.00AM) alert if you plan meticulously or On the day of event alert if you plan on the day.
#2: For Events that are time-specific, you’d want a 30-minute-prior (or lesser) alert.
#3: For All-Day Events, you obviously need just an on-the-day alert.
But of course, all this is just relative. You can set any specific alert time as per your preference.
Now all this is for individual events that you have on your calendar. Do these work on all calendars that you sync? Yes, irrespective of what account you sync from. Gmail, Exchange, iCloud, etc.
However, note that if you run into alert issues, you might want to check the event properties from the Calendar app itself. Suppose an event has an alert set to none within its preferences, you will not get an alert.