Why am I not running in a Microsoft Learn sandbox?

Question

I am doing a Microsoft Learn exercise that requires a sandbox (Exercise - Consume a REST service with HttpClient). I followed the directions to activate the sandbox, and signed in with my account ID and password. Then I got a message saying that "WARNING!!! It appears you aren't currently running in a Microsoft Learn sandbox. Any Azure resources provisioned by this script will result in charges to your Azure subscription."

What did I do wrong? The following is the content of my Azure Cloud Shell:

Requesting a Cloud Shell.Succeeded.

Connecting terminal...

Welcome to Azure Cloud Shell

Type "az" to use Azure CLI

Type "help" to learn about Cloud Shell

revans611 [ ~ ]$ git clone https://github.com/microsoftdocs/mslearn-dotnetmaui-consume-rest-services

Cloning into 'mslearn-dotnetmaui-consume-rest-services'...

remote: Enumerating objects: 169, done.

remote: Counting objects: 100% (169/169), done.

remote: Compressing objects: 100% (139/139), done.

remote: Total 169 (delta 44), reused 92 (delta 14), pack-reused 0

Receiving objects: 100% (169/169), 186.29 KiB | 16.93 MiB/s, done.

Resolving deltas: 100% (44/44), done.

revans611 [ ~ ]$ cd mslearn-dotnetmaui-consume-rest-services/src

revans611 [ ~/mslearn-dotnetmaui-consume-rest-services/src ]$ bash initenvironment.sh

initenvironment.sh: line 20: [: learn-e25b88f3-fb50-4f21-98f4-ba3664578958: unary operator expected

WARNING!!! It appears you aren't currently running in a Microsoft Learn sandbox. Any Azure resources provisioned by this script will result in charges to your Azure subscription.

Using Azure resource group consume-rest-services.

The webapp 'mslearnpartsserver12865476' doesn't exist

Operation returned an invalid status 'Forbidden'

Web app deployed! Here is the url to use in the app:

https://mslearnpartsserver12865476.azurewebsites.net

revans611 [ ~/mslearn-dotnetmaui-consume-rest-services/src ]$