Hi,
That policy has input parameter name operationName. So you should check first which of these operations were configured by the policy to check:
"Microsoft.Sql/servers/firewallRules/write",
"Microsoft.Sql/servers/firewallRules/delete",
"Microsoft.Network/networkSecurityGroups/write",
"Microsoft.Network/networkSecurityGroups/delete",
"Microsoft.ClassicNetwork/networkSecurityGroups/write",
"Microsoft.ClassicNetwork/networkSecurityGroups/delete",
"Microsoft.Network/networkSecurityGroups/securityRules/write",
"Microsoft.Network/networkSecurityGroups/securityRules/delete",
"Microsoft.ClassicNetwork/networkSecurityGroups/securityRules/write",
"Microsoft.ClassicNetwork/networkSecurityGroups/securityRules/delete"
After that you should configure activity log alert with conditions that it applies for Administrative category and operation name for example Microsoft.Network/networkSecurityGroups/delete. Note that when you configure the alert via portal these operation names has display names instead of the raw type if you hover the mouse over the display name you will see the type. For example, type Microsoft.Network/networkSecurityGroups/delete has display name "Delete Network Security Group (Network Security Group)". In case you have one or more policies assigned with different input for operatioName you will need to create alert rule for each operation. Also keep in mind that if the policy is assigned to more than one subscription you should create such alert rule for each subscription.
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