Microsoft 365 Alimentation d'un compte

Private Sub Worksheet_Change(ByVal Target As Range)
    If Not Application.Intersect(Target, Range("B1")) Is Nothing Then
        If Target <> "" Then
            Application.EnableEvents = False
            valsaisie = Target
            Application.Undo
            If IsNumeric(valsaisie) Then
                If Left(Target.Formula, 1) = "=" Then
                    Target.Formula = Target.Formula & "+" & Trim$(Str$(valsaisie))
                Else
                    Target.Formula = "=" & Trim$(Str$(valsaisie))
                End If
            End If
            Application.EnableEvents = True
        End If
    End If
End Sub