Microsoft Entra B2B guest invitations blocked due to suspicious activity

We are unable to invite any external users to our Microsoft Entra tenant. All B2B guest invitations fail with:

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

We are a small Swedish non-profit community association (Rossö Samhälls- och Fritidsförening). The association is entirely volunteer-run and non-commercial. We use Microsoft 365 and B2B guest access for legitimate collaboration with board members, members and volunteers.

During setup and testing we have invited and removed test guest accounts several times, which may have triggered the suspicious activity protection.

Our External Collaboration and Cross-tenant Access settings allow B2B collaboration, and the issue affects all guest invitations.

Could a Microsoft moderator please help us have the tenant reviewed and the B2B invitation block removed?

I can provide Tenant ID, request IDs, timestamps and administrator details privately if required.

@Sridevi Machavarapu
I noticed that you have helped with similar Microsoft Entra B2B invitation blocking cases before. If possible, I would be very grateful if you could take a look at this case or help point it to the appropriate internal team. Thank you.