Entra ID Member and Guest Invitations Blocked – Suspicious Activity Flagged

Hello Microsoft Support,

We are experiencing a tenant-level block on guest invitations in our Azure AD / Microsoft Entra ID directory.

All invitations (both Graph API and Azure Portal) are failing with the following error:

Invitations are blocked for this directory due to suspicious activity. Please contact Microsoft support for help.

Situation

We are Global Administrators on the tenant and recently performed a series of User invitations scenarios in our internal testing environment using a custom integration with the Graph API.

After several user invitation batches within a short timeframe, all invitations became blocked, including manual invitations.

Impact

Guest invitations are completely disabled for the directory and we cannot onboard legitimate test environment user accounts.

This in turn is blocking feature development and QA responsibilities.

Request

Could you please:

1. Review and remove the suspicious activity block on guest invitations
2. Provide a resolution to the tenant being blocked from User additions

We would greatly appreciate urgent assistance in restoring invitation functionality.

Thank you.