Issue
When using LazyApproval with Nintex for Office 365, if the task assignee has an 'out of office' response, the LazyApproval system sends a second email saying that their response was not valid.
Resolution
This is currently expected behavior within Office 365, as LazyApproval within Office 365 currently does not support LazyApproval. There is a feature request for this functionality which can be found here.