I travel from Alfreton to Nottingham and use the ticket office. If unavailable the ticket machine only sells the more expensive East Midland Train ticket even though I am using a Northern Rail service for my return journey. I have raised the issue and I was advised by a ticket collector I could buy a ticket on the train. I have done so routinely without issue on a number of occasions until my last journey when I was issued with a penalty fare. I appealed and the appeal was refused. Can anyone help or advise?