If you no longer have this, please telephone the Customer Contact Centre on 0300 062 5004 and tell the operator your CRN.
Os nad yw’r wybodaeth hon gennych mwyach, ffoniwch y Ganolfan Cyswllt Cwsmeriaid ar 0300 062 5004 a rhowch eich Cyfeirnod Cwsmer i’r gweithredwr.