compile error : Ambiguous name detected: Worksheet_Change

I was using VBA code for Timestamp And move row to another worksheet. I was using Below codes successfully working individually, but two codes entered in worksheet module not working.

I hope you help me.

 Private Sub Worksheet_Change(ByVal Target As Range)
  If Intersect(Target, Range("A1")) Is Nothing Then Exit Sub
    If Target.value = "" Then
      Range("B1").value = ""
    Else
      Range("B1").value = Format(Now, "dd/mm/yyyy HH:mm:ss AM/PM")
    End If
  
End Sub

Private Sub Worksheet_Change(ByVal Target As Range)
    If Intersect(Target, Range("g:g")) Is Nothing Then Exit Sub
    Application.EnableEvents = False
    If Target = "yes" Then
        Target.EntireRow.Copy Sheets("s2").Cells(Sheets("s2").Rows.Count, "A").End(xlUp).Offset(0)
    End If
    Application.EnableEvents = True
End Sub

Each sheet can have only one Worksheet_Change event sub, which is why you're seeing a compiler error. However, you can merge your two scripts into a single Worksheet_Change event.

Note: Offset(0) means no offset, so the code below overwrites the last data row on sheet s2, which is likely not the intended outcome. Changing it to Offset(1) will copy the data to the first blank row.

Target.EntireRow.Copy Sheets("s2").Cells(Sheets("s2").Rows.Count, "A").End(xlUp).Offset(0)

Private Sub Worksheet_Change(ByVal Target As Range)
    Application.EnableEvents = False
    If Not Intersect(Target, Me.Range("A1")) Is Nothing Then
        If Target.Value = "" Then
            Me.Range("B1").Value = ""
        Else
            Me.Range("B1").Value = Format(Now, "dd/mm/yyyy HH:mm:ss AM/PM")
        End If
    End If
    
    If Not Intersect(Target, Me.Range("g:g")) Is Nothing Then
        If Target.Value = "yes" Then
            Target.EntireRow.Copy Sheets("s2").Cells(Sheets("s2").Rows.Count, "A").End(xlUp).Offset(1)
        End If
    End If
    Application.EnableEvents = True
End Sub

Microsoft documentation:

Range.Offset property (Excel)