how do i Eliminate multiple Entries in GridView Telerik

I am Working on Windows Form Telerik. As I have Grid View of Telerik Control and i want to add New Entry into that. I have Button for create new Entry Click on that button Winform will popup and on that popup if i click on save it will add that row. But My Problem is that 1 Row added with that another Row also add which is not required.

My Code Is Below. public void Save(TimesheetEntry timesheetEntry) { if (timesheetEntry.TimesheetEntriesId == -1) { timesheetEntry.SequenceNumber = GetNextSequenceNumber(timesheetEntry.FileId, timesheetEntry.EntryDate); Add(timesheetEntry);

      }
      else
      {
          Update(timesheetEntry);
      }
      //Audit trail
      //TODO:
      //MyAuditTrialModel.Add<TimesheetEntry>(Helper.Actions.CU_Timesheet, Helper.TableNames.TimesheetEntry, timesheetEntry);
  }</pre>

This one is Add Method:

  <pre lang="cs">private TimesheetEntry Add(TimesheetEntry item)
   {
       _context.TimesheetEntries.AddObject(item);
       _context.SaveChanges();
       return item;
   }</pre>

And On Edit Button also it will Generate 2 rows. which code is as below.

 <pre lang="cs">private TimesheetEntry Update(TimesheetEntry item)
   {
       _context.TimesheetEntries.ApplyChanges(item);
       _context.ObjectStateManager.ChangeObjectState(item, System.Data.EntityState.Modified);
       _context.SaveChanges(true);
       return item;
   }</pre>