I have nintex workflow  with 2 steps. 1. manager approval 2. Update listitem. When manger does approval on Website workflow completed successfully. When Manager does Lazy approval,  both steps are completed but workflow ended up with following error. Any suggestions plz.

10/13/2015 11:07:27.21 OWSTIMER.EXE (0x2FB8) 0x57C0 SharePoint Foundation Legacy Workflow Infrastructure 98d4 Unexpected System.NullReferenceException: Object reference not set to an instance of an object.     at Microsoft.SharePoint.Workflow.SPWinOEWSSService.GetWebForWorkflow(SPWorkflow wf, SPWorkflowUserContext runAsUser)     at Microsoft.SharePoint.Workflow.SPWinOEWSSService.get_Web()     at Microsoft.SharePoint.WorkflowActions.WorkflowContext.get_Web()     at Nintex.Workflow.Activities.ReportingActivity.Execute(ActivityExecutionContext executionContext)     at System.Workflow.ComponentModel.ActivityExecutor`1.Execute(T activity, ActivityExecutionContext executionContext)     at System.Workflow.ComponentModel.ActivityExecutorOperation.Run(IWorkflowCoreRuntime workflowCoreRuntime)     at System.Workflow.Runtime.Scheduler.Run() 9c26379d-8b21-4012-9b28-be808f6aa674

Regards,

Gunesh v