If an Alert has been accepted by any recipient, you can leave the Alert. You can complete an Alert if you have accepted the Alert, if you originated the Alert, or if you have the necessary administrative permissions.
To leave an Alert, tap Leave.
To complete an Alert, tap Complete. This completes the Alert for everyone who has received it.
To leave or complete an Alert from the Home screen, press and hold on the Alert. A dialog box appears, asking you whether you want to leave or complete the Alert.
The Complete option appears if you have the right to complete the Alert. Otherwise, the Leave option appears.