Hello Felipe Eduardo Campelo,
Thanks for your question.
No you do not need a subscription to use Azure Sandbox. Try the following steps:
- Sometimes, clearing the browser cache and cookies can resolve loading issues. Sign-out from all the tabs in the current browser and clear the cache files and try login again with your learn id credentials.
- Try a new browser maybe Edge? or try in an inprivate window.
See: https://zcusa.951200.xyz/en-us/azure/cloud-shell/faq-troubleshooting#managing-cloud-shell
You can mark it 'Accept Answer' and 'Upvote' if this helped you
Regards,
Abiola