This error occurs when the crm_integration user in Luminate Online does not have the correct Recurring Gift permissions. To solve it do the following:
  1. Find the Luminate Online Administrator Group that the crm_integration user is in (it should be the API Administrators group)
  2. Go to the Group Permissions tab and choose Recurring Gifts from the drop-down
  3. Set the Default Permissions to Recurring API and Save