Problems using IF statement in DO WHILE loop

[walneyhammer]

Good Evening, Im hoping you can assist me

I have the following loop that should look through my rows of data for the Value "Y" in column T, for those rows that contain "Y" it should update column K with the variable xdate

For some reason it doesn't seem to work, it changes the first entry it finds and then seems to crash, I have to use CTRL+BREAK to stop it.

Please can you help and let me know what I'm doing wrong ?

Private Sub changedate_Click()
Dim xdate As long
Dim iBegin As Integer
Dim iEnd As Integer

          
Application.ScreenUpdating = False
    On Error GoTo GetOut:
    iBegin = 5 ' This is the row that the list starts
    iEnd = Sheets("Bookings").Range("B4").End(xlDown).Row
    

    MyNote = "Are you sure you wish to change the date for all marked bookings ?"

    'Display MessageBox
    Answer = MsgBox(MyNote, vbQuestion + vbYesNo, "Confirm Date Change")
    
    If Answer = vbNo Then
        'Code for No button Press
        GoTo GetOut
    Else
    
                xdate = InputBox("Please enter new date", "New Date Entry", "dd/mm/yy")
               
    
   Do While iBegin <= iEnd
        With Sheets("Bookings")
            If Cells(iBegin, 20).Value = "Y" Then
               Cells(iBegin, 11).Value = CDate(xdate)
            Else
                iBegin = iBegin + 1
            End If
        End With
    Loop

Many thanks, Darren