Scheduling atom in v18

Need to schedule a atom to run in particular time. made changes in the xenv-tasks.xml(here specified the chain name and time interval) and in actions.properties(specified permitted time to run the atom), but the atom is running only when launching environment otherwise it is not.

<bean id="startrunningtrainingdbbackup" class="oracle.retail.xenvironment.scheduledtasks.ScheduledTaskProcessor">

    <property name="actionName" value="RESTORE_DB_TRAINING" />

    <property name="runOnRole" value="LEAD" />

  </bean>

<task:scheduled ref="startrunningtrainingdbbackup"

                    method="runTask"

                    fixed-rate="#{xenvConfig.getScheduledTaskFixedRateMillis('startrunningtrainingdbbackup', 600000)}"

                    initial-delay="#{xenvConfig.getScheduledTaskInitialDelayMillis('startrunningtrainingdbbackup', 120)}" />

  </task:scheduled-tasks>

actions.properties:

chain.RESTORE_DB_TRAINING.permitted_start_times=*,15:15,2

how i need to schedule to run at particular time.