Calendar Reminder Alerts not sounding

I seem unable to get Reminder Alerts to sound and have missed important stuff because of it.

Calendar Notifications are ON, a sound has been selected and alerts sound for Events - just not reminders.

It's a new iPhone 15 Plus, Calendar is linked to iCloud, Do Not Disturb is OFF, sounds are ON and sound for everything else.

The iOS is up-to-date and the phone haas been restarted twice.

Help🙏