Dear Nintex community,
We got some details that using the SOAP method ProcessFlexiTaskResponse2, we can do that. We were successful in approving the workflow from SOAPUI but we are looking for the equivalent REST service which can allow us to approve the workflow item from our program.
Thanks for your time and help.
that's the point, for workflows on SP2013 on-prem there is provided just SOAP webservice.
REST service is provided for forms.
REST webservice for workflows is currently provided only on O365.