Your users must meet minimum age requirements to use Google+. If a user who's attempting to sign up for Google+ enters a birthday that indicates they don't meet the age requirements for Google+, the user's entire G Suite account—including Gmail and other services—will be disabled. The user won't be able to sign in to their G Suite account.
In case the user entered an incorrect birthday, Google provides a 30-day grace period during which the administrator can confirm that the user made an error and submit the correct birthday. After the grace period, a user's suspended account will be permanently deleted.
If you have the legacy free edition of G Suite, upgrade to G Suite Basic to get this feature.
To correct a user’s age and recover a suspended account:
- Verify the user’s actual birthday to see if the user made an error. If so, continue with these steps.
- Sign in to the Google Admin console.
- Find the user’s account and open it.
- In the suspension warning message that appears at top, click Update user's birthdate.
- Enter the user's correct birthday and check the box to verify the new date.
- Click Submit.
The account suspension is lifted and the user's access to G Suite services is restored.