Calendar: The request was denied by service delegate

Hello,

Over the past two days my wife (iPhoneX) and my iPhone 11 Pro both on the latest software (14.0.1) have recieved Notifications from Apple Calendar that say "The request was denied by service delegate... The request to open "com.apple.mobilecal" failed". If you click to view the notification from the notification centre, the message just disappears and takes you no where. Should we be worried that somone/something is trying to access our calendars?