National Geographic International refund.

Hello.

My National Geographic magazines are no longer available. From National Geographic (NG) International said I need to address Apple for the subscription issue and that all subscriptions were canceled. This ultimately means I will no longer be able to access any of the magazines I purchased. I believe I had two years of subscription. I would like to have a refund my National Geographic subscription and I need to address Apple for my refund. How could I apply for the refund because any information about NG international subscription is no longer visible on my iTunes purchases page? Thank you.