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About the AADSTS5000225 error (tenant blocked due to inactivity) that you encountered, please let me recommend you few steps to help you.
1. Check Tenant Status
Sign in to the Azure portal with a Global Administrator account and check the Azure AD tenant status.
2. Reactivate the Tenant
If the tenant is marked as blocked, you will need to contact Microsoft Support to request reactivation. Ensure having your Tenant ID and subscription information ready.
3. Verify Subscription State
Ensure the subscription associated with the tenant is active. If it’s expired or disabled, renew or reactivate it first.
4. Check User Accounts
Once the tenant is unblocked, verify that user accounts are enabled and that required roles/permissions are assigned.
5. Test Sign-in
Try signing in again to confirm the issue is resolved. If the error persists, review Azure AD sign-in logs for additional details.
Note: Only a Global Administrator can manage or request changes to tenant status. If you don't have this role, please contact your organization’s Azure AD admin.
Thank you for your question and I hope you have a good day!