Organization validation: "You need permission", signed in on "Microsoft Accounts" tenant instead of our directory

Our organization identity validation (Public, United States) is in "Action Required", but we cannot open the verification link.

The link redirects to credentials.microsoft.com/verify/noPermission and shows "You need permission". It says we are logged in on Entra tenant "Microsoft Accounts", although the signed-in email matches the primary email on the request.

Setup:

• The account was created through Azure pay-as-you-go signup, using a company-domain email as a Microsoft account.
• The subscription and the Artifact Signing account are in our organization's directory, which is the account's only directory and the current one.
• The account has Owner on the subscription and Artifact Signing Identity Verifier on the signing account.

Already tried: a clean InPrivate session, signing in to the portal first and opening the link from the validation panel, and signing in through "Sign in to an organization" with our onmicrosoft.com domain. The result is the same each time.

We do not have a paid support plan, and the 7-day verification window is running.

Questions:

1. Can a Microsoft staff member check how this validation is bound to our tenant and correct it or reissue the link? We can share the validation ID and tenant ID privately.
2. Can a Microsoft account complete this step, or must it be a member work account in the directory? If so, what should we do about the primary email already on the request?