Please refer my previous article to learn more about creating NINTEX workflow in SharePoint 2013 Online.
In this blog you will see how to remove group using NINTEX workflow in SharePoint 2013 Online.
We will be removing the group from SharePoint site by calling the web service _vti_bin/usergroup.asmx. I have created a list which contains Name – Single line of text andComments – Multi line of text field.
Web Request Action:
Set Field in Current Item Action:
The group name specified in the "Name" field is removed successfully from the SharePoint site.