Hi Russ,
Thank you for asking this question on the Microsoft Q&A Platform.
Apologies for the inconvenience you are experiencing due to issues in accessing the sandbox.
Please note that only 20 sandboxes are available per day. Check your usage quota, and if the sandbox has already been activated but is now closed, reactivate it before continuing.
We have successfully activated the sandbox as illustrated in the screenshot provided below for your reference:
Note: As a workaround, kindly refresh the page and check whether the issue still exists.
we request you to try the following steps before you try to activate a sandbox.
Step 1: Sign-out from all the tabs in the current browser and clear the cache files and try login again with your learn id credentials.
Step 2: Sign-out from current browser login and try to login from an incognito window/in-private window.
Step 3: Switch to a different browser and try login again.
Step 4: Login with a new personal email account into the learn path in a completely new browser and check.
If the information is helpful, please accept the answer by clicking the "Upvote"/ "Accept Answer" on the post.
If you are still running into issues, kindly attach the screenshots for reference and please let us know in the comments. We are glad to help you.
Thank you.