Code request to delete numbers in column B automatically

Hi,
Please suggest me a code to delete the serial number in column 'B' if the cell in column 'C' is blank or I deleted the value in column 'C'.

Private Sub Worksheet_Change(ByVal Target As Range)
'AutoSerialNumbers
    With Range("B6")
        .Value = "1"
        .AutoFill .Resize(Range("c" & Rows.Count).End(xlUp).Row - .Row + 1), 2
    End With
    MsgBox "Done!", 64
End Sub

In short if the cell in column 'C' is blank then there should not be a serial number in column 'B'. The code should run only when there is a value in column 'C' automatically. I want to insert this code in sheet module to run it automatically after theere is any change in column 'C'.

Any help will be appreciated.

Thanking you,

Something like this will clear the cell from column B anytime you clear a cell in column C.

Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
Dim cell As Range

If Not Intersect(Target, Range("C:C")) Is Nothing Then
    For Each cell In Intersect(Target, Range("C:C"))
        If cell.Value = "" Then Range("B" & cell.Row).ClearContents
    Next cell
End If

End Sub

I have integrated the 2 codes but now I'm getting compile error 1004:
auto fill method failed

on line

.AutoFill .Resize(Range("c" & Rows.Count).End(xlUp).Row - .Row + 1), 2

If I delete the entire column 'C' then this error occurs.

Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
Dim cell As Range

If Not Intersect(Target, Range("C:C")) Is Nothing Then
    For Each cell In Intersect(Target, Range("C:C"))
        If cell.Value = "" Then Range("B" & cell.Row).ClearContents
        With Range("B6")
        .Value = "1"
        .AutoFill .Resize(Range("c" & Rows.Count).End(xlUp).Row - .Row + 1), 2
    End With
        Next cell
End If
MsgBox "Done!", 64
End Sub

Thanking you.