Trusted Signing organization identity validation stuck in In Progress, will not complete

Our organization identity validation for Trusted Signing stays in the In Progress state and never moves to Completed.

We submitted all three requested documents and they were accepted (green checks): domain ownership records, an assignment letter from an authorized representative, and a domain purchase invoice.

The validation pane keeps asking us to complete email verification. But this was already done: the verification message was delivered to our primary mailbox, and the completion link now says it has already been used. So email verification is complete, yet the status will not change to Completed.

How can we get the validation finalized, or have a new verification link issued? I can share the validation ID and account details privately with a Microsoft engineer.

Thank you.