If you encounter the error "Provided calendar_id does not exist," there may be an issue with your calendar integration. Try the following steps: disconnect your calendar and then reconnect it under the Scheduler Settings. Ensure you're using a supported calendar provider. Currently, we support Gmail, Google Apps, Microsoft Exchange, Office365, Outlook.com, and Yahoo! Mail. Double-check that you've completed all steps in the calendar integration process, including granting Tern the necessary permissions. If the issue persists, please contact our support team for further assistance.