Search Calendar Events - Subject

I am trying to search for a calendar event with subject that contains "PBG ({{a.pbg_number}}) Followup Reminder" and delete.

When I enter the Subject field (one below Calendar) as "PBG ({{a.pbg_number}}) Followup Reminder User" (without quotes), then the pipeline couldn't find any match. 

But when I add a condition like below snapshot it finds 6 matches but keeps running in a loop and pipeline doesn't stop.

Can you help me fix this?

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Anitha Jeevarathinam
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