Please be sure you have two-factor authentication enabled. As of June 15 Apple is requiring that iCloud accounts have two-factor authentication enabled in order to use apps such as Fantastical. Please see our iCloud page for more info. This is a change by Apple to increase security, this is not something we can disable.
Have a question? Check the Frequently Asked Questions as it may already be answered. If it's not, please don't hesitate to contact us.
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