shipment = Mollie::Order::Shipment.update(
  'shp_3wmsgCJN4U',
  order_id: 'ord_kEn1PlbGa',
  tracking: {
    carrier: 'PostNL',
    code: '3SKABA000000000',
    url: 'http://postnl.nl/tracktrace/?B=3SKABA000000000&P=1016EE&D=NL&T=C'
  }
)