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Login to Azure Portal using https://portal.azure.com.
Go to Application security groups.
Click on the application security group that reported to delete the rule.
In the network security group's menu bar, choose Inbound security rules.
In the left menu, under the Security section, click Advanced security.
Select the rule which allows access from any (*) source address.
Select Delete, and then select Yes.
Important:
Remediating Deletion of rule may result in user losing some connection whose IP is not whitelisted in rules
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