Provide an option to unlock locked accounts without having to wait for 24 hours. Also what does the statement "account will re-open within 24 hours mean?".. Do you keep expecting the users to keep trying to login every 15 minutes or an hour or a couple of hours to check if the account is unlocked? You need to provide an adhoc option to unlock accounts as and when users request the same
Kindly help to unlock the account as it is not getting unlocked even after 24 hours.