Now you might be wondering how you can delete an existing Nintex Workflow that you're no longer using. You can do this through the List or Library Settings of the list/library the workflow sits on, this option is a part of the SharePoint interface.
In the List/ Library settings page, you should see the option Workflow Settings, click on it. This page will show you any workflows that are associated with this list or library. Now to delete a workflow, click on Remove, Block or Restore a Workflow.
On the Remove Workflows page, select either "No New Instances" or "Remove" to delete a workflow.
- No new instances = Allows any running workflows to complete, but prevents any new workflows to be started.
- Remove = will cancel any running workflows.