Invalid API call as no apiproduct match found

After setting up a business account and having billing set to Telstra Account:

Retrieving a token succeeds however the scope returned doesn't match the scope requested (as per documentation):

% curl -X POST -H 'Content-Type: application/x-www-form-urlencoded' \ -d "grant_type=client_credentials&client_id=$CLIENT_KEY&client_secret=$CLIENT_SECRET&scope=NSMS" \ 'https://tapi.telstra.com/v2/oauth/token' {"access_token":"XXXXXXX","token_type":"Bearer","expires_in":"3599","scope":""}

Making a call to attempt to provision a service results in the apiproduct match found error:

% curl -X POST https://tapi.telstra.com/v2/messages/provisioning/subscriptions -H "authorization: Bearer $ACCESS_TOKEN" -H 'cache-control: no-cache' -H 'content-type: application/json' -d '{ "activeDays":30, "notifyURL":"http://example.com/" }' { "status":"401", "code":"TECH-ERR", "message":"Technical error : Invalid API call as no apiproduct match found : An error has occurred while processing your request, please refer to API Docs for summary on the issue" }

The documentation says:

If the problem persists, write a post in the Messaging API forum

So here we are, can you please help? We've been trying to provision an SMS service for over a month now, this doesn't seem like a difficult thing to provision (plenty of other providers are 5 minute setups).