The error interaction_required: AADSTS5000225: This tenant has been blocked due to inactivity means the Azure AD tenant behind the account has been marked inactive and blocked, so interactive sign-in to Azure (including ai.azure.com and portal.azure.com) no longer works.

From the documented behavior and similar cases, there are only a few viable paths:

1. Check if the tenant can still be reactivated (blocked < 20 days)
   If the tenant has only recently been blocked, administrators can request reactivation within 20 days of entering the inactive state. After 20 days, the tenant is permanently deleted and cannot be recovered. Actions:
   • Try signing in explicitly with the tenant in the URL, for example:
     https://portal.azure.com/<TenantId> or https://portal.azure.com/<yourTenantName>.onmicrosoft.com
     (replace with the actual tenant ID or onmicrosoft.com name).
   • If sign-in still fails with the same error and the tenant is within the 20‑day window, the tenant administrator must contact Microsoft using the global support phone numbers to request reactivation. See the guidance under Tenant inaccessible due to inactivity.
2. If the tenant has been blocked for more than 20 days
   In this case, the tenant is on the path to, or has already been, permanently deleted and cannot be restored. The documented guidance is:
   • The tenant cannot be recovered after 20 days from the block being applied.
   • To continue with Azure training, use a different active tenant or create a new one.
3. Workaround used in similar free‑trial scenarios
   For some users whose free trial tenant was blocked, the following sequence allowed them to proceed:
   • Open a Chrome (or other browser) incognito/private window.
   • Clear all browser data (cookies, cache, site data) for Microsoft/Azure sites.
   • Go to the Azure signup page (signup.azure.com as per the documented case) and sign in with the same Microsoft account that shows the inactivity error.
   • The system may recognize an existing free account and prompt to “upgrade” to a pay‑as‑you‑go account (often still effectively at a basic/no‑charge level until usage exceeds free limits). Completing this flow re-established access for that user in the referenced case.
4. If still blocked and no admin or support path is available
   • For training purposes (Microsoft Learn / Azure AI Fundamentals), the practical option is to create or use a different Microsoft account that backs a new, active Azure tenant, then sign in to the labs with that account.

Because this is a tenant‑lifecycle enforcement, it cannot be fixed purely from the portal UI if the tenant is beyond the reactivation window; it requires either Microsoft support intervention within the allowed time or using a different/new tenant for the course.

References:

• Troubleshoot Azure subscription sign-in issues
• Troubleshooting common training issues in Microsoft Learn
• Troubleshoot sign in issues for support.microsoft.com
• Troubleshoot sign-in issues and account access problems
• Common problems with two-step verification for a work or school account
• I can't sign in to my Microsoft account
• Sign into Azure interactively using the Azure CLI
• Error message: AADSTS5000225: This tenant has been blocked due to inactivity. - Microsoft Q&A
• 7 Day Old Azure Account: AADSTS5000225: This tenant has been blocked due to inactivity. - Microsoft Q&A
• Error message: interaction_required: AADSTS5000225: This tenant has been blocked due to inactivity - Microsoft Q&A
• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A
• Can not access Azure - Microsoft Q&A