A fully managed end-to-end service for digitally signing code, documents, and applications. (formerly Trusted Signing)
Because the operation fails through both REST and SignTool while the resource, profile, certificate, role, and subscription are healthy, this strongly indicates service-side state rather than client configuration. Artifact Signing has no documented customer command to clear a post-suspension hold or force reissuance.
Open an Azure technical support request from the affected paid subscription and select Artifact Signing. Include the subscription ID, account/profile names, endpoint, disable/reactivate timestamps, several failed operation IDs with UTC times, and the null response. Add a unique CorrelationId to one new request. Ask the service team to inspect data-plane eligibility, certificate issuance/rotation, and any suspension flag, then re-enable or reprovision the backend state.
Do not delete the account or profile while the case is open; deletion stops renewal and removes useful evidence. The West US 2 endpoint is correct, and direct REST reproduction largely rules out the dlib, SignTool, or local runtime.