Hello jwnead,
We understand you haven't been able to change the notification sound for your calendar notifications on your iPhone. We have steps to walk through to make sure you didn't miss anything when checking your settings. If you are using a third-party calendar app, you may need to check with that app developer.
How to contact an app developer
For the Apple Calendar app, we'll use this guide as a reference: Change notification settings on iPhone
- Go to Settings > Notifications > Calendar.
- Tap Sounds.
- Test notifications with None set for the alert tones (vibrate only).
- If you want to test a different alert, make sure it is from the Alert Tones section.
If the alert still won't change regardless of what shows in Settings, we'd next recommend reaching out to our support teams directly. You can reach them here: Get Support - Apple
You can also find our phone number for your region at this link: Contact Apple for support and service
All the best.