Enable SMS Sign out reminders
To setup the system to send SMS sign out reminders, first click on the “Configure System” section of the dashboard and then “SMS Settings“.
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You will be presented with a list of different settings to change and there should be one titled “Send an SMS reminder to visitors to sign out”.
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Change this setting to the time you would like visitors the reminder to be sent and then click the “Update changes” button at the top of the screen.