Why while uploading Collection getting Error "Signing %s service not found" ?

Issue

• While uploading the collection on Private Automation Hub getting the below error:

  Oct 21 00:59:28 tower.example.com pulpcore-worker[545739]:    result = func(*args, **kwargs)
  Oct 21 00:59:28 tower.example.com pulpcore-worker[545739]:  File "/usr/lib/python3.9/site-packages/galaxy_ng/app/tasks/publishing.py", line 103, in import_and_auto_approve
  Oct 21 00:59:28 tower.example.com pulpcore-worker[545739]:    raise RuntimeError(_('Signing %s service not found') % SIGNING_SERVICE_NAME)