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Garmin Connect App: “Sign in Failed. Cannot Sign In. Try Again Later”
The error message “Sign in Failed. Cannot Sign In. Try Again Later” happening in the Garmin Connect™ app is due to a content filter setting on your iPhone. To resolve this, you will need allow Garmin websites in your phone's Content Restrictions settings. To update your iPhone's settings:
Open the iPhone Settings app.
Select Screen Time.
Select Content & Privacy Restrictions (enter Screen Time passcode, if necessary).
Select Content Restrictions.
Select Web Content.
Select Add Website.
Enter https://www.garmin.com/ for the URL.
Select Done.
You will now be able to sign into the Garmin Connect™ app on your iPhone. For more information about updating Content & Privacy Restrictions, see https://support.apple.com/HT201304