Blocking Sessions alerts are not getting invoked by Powershell script

Hi All,

     Need some help ,  we are running a Powershell script  that picks up the alerts  from idera . We are getting   all the alerts with powershell script  but only Blocking session  are not getting alerted . When we looked up the   SQLDM DB  the alert table we noticied that it was showing a error " Error excecuting power shell alert script [Test] on [C:\Users\Administrator\Downloads\acn_infra360db-idera_adc_win-x86-64\bin\IDERA_Only_Log.ps1 -AlertSummary "Session 57 blocking for 52 seconds, since 5/23/2022 3:03:32 PM." -AlertText "SQL Server instance" .   Has anyone faced this issue . Help is much appreciated ?