Required Learning Assignment notifications are not triggering for some users

Hi,

We have an alert "Required Learning Assignments" which needs to be triggered when an new required learning assignments are assigned to learners. But notifications are not triggering for few users.

Below are the Filter conditions used:

exists (SELECT 'x' from dual where ${assignmentCreatedDate} >= (select nvl(max(runs.run_end),sysdate-1) from hrc_alert_runs runs, hrc_alerts_b alerts where runs.alert_id = alerts.alert_id and alerts.alert_code = 'Alert Code Here'))

${assignmentStatus}='ORA_ASSN_REC_ACTIVE'

${assignmentCreatedDate}>=sysdate-1

${assignmentType}='ORA_REQUIRE_ASSIGNMENT'

kindly help whether exists clause is causing the issue