SEM 2020.4.1 User Lockout Rule Sometimes Fires Twice And Sends Two Emails

I have agents on 4 domain controllers.

Sometimes the rule fires once and only 1 email is sent but sometimes it fires twice so we receive 2 emails. 

In the User Account Lockout rule I have the "Set time when a rule won't trigger actions after rule was true" checked and set for 30 seconds. When the rule fires twice they are only a second or so apart and are from different domain controllers so I don't know how to change it to prevent it from firing more than once for the same user account that is getting locked out.