Stage | Confirmation Statement | server error

Environment: stage
Company: UK Benefits for Hspl
Login: Employee
User name: hspl6612
Password: Password@1
1.Login as employee
2.go to confirmation statement

actual result: server error occur on confirmation statement page
expected result: confirmation statement page should be open

error log: Exception : String was not recognized as a valid DateTime.
App Error Log : -
Employee ID : 6610
Action Name : EmployeeInfo
Model : System.Web.Mvc.HandleErrorInfo
Controller : UserDetails
Web Error Log : at System.DateTimeParse.ParseExact(String s, String format, DateTimeFormatInfo dtfi, DateTimeStyles style)
at WORKTERRA.SharedFunctionWebTier.ConvertToGetDateFormat(String ControlValue, String InputFomat)
at ASP.Page_Areas_UserDetails_Views_UserDetails_EnrollmentSummary_EnrollmentSummaryEmpInfoPV_cshtml.Execute() in c:\Workterra Web\BenAdmin\Areas\UserDetails\Views\UserDetails\EnrollmentSummary_EnrollmentSummaryEmpInfoPV.cshtml:line 161
at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
at System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context)
at System.Web.Mvc.ControllerActionInvoker.<>c_DisplayClass1a.b_17()
at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult)
at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName)