Apple requires an app-specific password for your iCloud account in order to use Fantastical. You can generate an app-specific password after you enable two-factor authentication on your iCloud account.
We have a short video tutorial on how to enable two-factor authentication and generate an app-specific password for Fantastical. It takes about 5 minutes to complete this process.
Make sure you are using your Apple ID's primary email address. You can check which email address is your primary address at appleid.apple.com.
If the iCloud account listed in Fantastical's preferences does not match your Apple ID's primary email address, remove the account from Fantastical and re-add it using the primary email address.
Next, make sure you have generated an app-specific password for Fantastical:
If Fantastical still says your password is incorrect, try the following:
Fantastical uses your iCloud password to ensure that your events and reminders are kept in sync with iCloud. Fantastical only uses your password to connect to iCloud, your password or data is never sent to Flexibits or any other third party.
Please see our privacy page for more information about privacy with our apps.