Hello @Sara Amini,
Thank you for connecting offline to check the issue.
The issue you were facing occurred because your tenant was identified as having a billing account associated with a company name listed as "Contoso" or "Microsoft," which caused it to be blocked. To resolve this, we reached out to the Product Group team internally. They have since unblocked your tenant, and as you confirmed, you are now able to access it successfully.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Thanks,
Raja Pothuraju.