Unable to access Log Analytics demo environment from Microsoft KB

Question

I am trying to access the Log Analytics demo environment from
https://learn.microsoft.com/en-us/training/modules/construct-kusto-query-language-statements/2-understand-kusto-query-language-statement-structure

but i am getting the error below.

There was an authentication problem. Try signing out and signing in again

Access to workspace 'CH1-LA' from '219.75.37.161' is denied. To allow access from public networks, change the workspace Networking settings or add it to a Network Security Perimeter. (workspace resource ID: /subscriptions/ebb79bc0-aa86-44a7-8111-cabbe0c43993/resourceGroups/ch1-opsrg-pri/providers/microsoft.operationalinsights/workspaces/CH1-LA)

If the issue persists, please open a support ticket. Request id: 15991cbe-179b-4933-b296-3b4090486784