Calendar 問題 - MAC

本來用都好好的
這幾天突然每次打開 calendar 都會又下列錯誤訊息:

The server responded with an error.

The URL https://calendar.google.com/calendar/dav/[email protected]/user/
encountered HTTP error 404. Make sure the URL is correct.

誰能幫忙
謝謝

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