hi all,

i facing the problem to lock the cell.
i am no idea how to lock the cell without sheet protected.

please help.
] 

Private Sub Worksheet_Change(ByVal Target As Range)
   LastRow = ActiveSheet.UsedRange.Rows.Count
   
If Not Intersect(Target, Range("B1:B" & LastRow)) Is Nothing Then
Range("C" & Target.Row) = ""
End If


If Not Intersect(Target, Range("D1:D" & LastRow)) Is Nothing Then

    If Range("D" & Target.Row) = "In Progress" Then
    Range("T" & Target.Row) = Format(Date, "YYYY-MM-YY")
    Range("V" & Target.Row) = "55"
    Range("U" & Target.Row) = "55"
    Range("V" & Target.Row).Locked = True
    Range("U" & Target.Row).Locked = True
    
    ElseIf Range("D" & Target.Row) = "Repaired" Then
    Range("V" & Target.Row) = Format(Date, "YYYY-MM-YY")
    Range("T" & Target.Row) = ""
    Range("U" & Target.Row) = ""
   
    
    ElseIf Range("D" & Target.Row) = "Checked" Then
    Range("U" & Target.Row) = Format(Date, "YYYY-MM-YY")
    Range("T" & Target.Row) = ""
    Range("V" & Target.Row) = ""
    
    ElseIf Range("D" & Target.Row) = "Unknown/Cancel" Then
    Range("V" & Target.Row) = Format(Date, "YYYY-MM-YY")
    Range("T" & Target.Row) = ""
    Range("U" & Target.Row) = ""
    
    End If


End If


End Sub