See solution below.
Explanation
1. Open Microsoft Azure Portal and Log into your Azure account.
2. Select network security group (NSG) named az400-9940427-nsg1
3. Select Settings, Outbound security rules, and click Add
4. Click Advanced

5. Change the following settings:
Destination Port range: 8080
Protocol. TCP
Action: Allow
Note: By default, Azure DevOps Server uses TCP Port 8080.
References:
https://robertsmit.wordpress.com/2017/09/11/step-by-step-azure-network-security-groups-nsg-security-center-az
https://docs.microsoft.com/en-us/azure/devops/server/architecture/required-ports?view=azure-devops