Hi Carlos,
You can workaround the issue by opening up a new tab and activating sandbox using below link:
Once you have successfully completed the puzzle, accepted permissions, etc., and sandbox is activated, complete the tasks as described in Exercise - Explore the Learn sandbox. Additionally, you may leave the tab open and use the same sandbox for the Exercise - Create an Azure resource later in same module.
NOTE: You may complete exercises using your Azure for Students subscription, however, you will need to make some adjustments to the instructions. For example, when using sandbox a resource group is created automatically whereas when using your own subscription you must create the resource group yourself. For exercises that have copy/paste code, you need to substitute the resource group name for the one you created. The above is only a portion of small adjustments that will be needed.
Of course when using your own subscription it is critical that you delete resource group after completing each module to avoid unnecessary charges.
Please click Accept Answer and upvote if the above was helpful. If something is unclear or you need additional assistance please add a comment below.
Thanks.
-TP