If you purchased an unlimited faxes subscription and would like a refund, you must contact Apple directly, as they do not provide us with the ability to process refunds. Only Apple can process refunds for purchases made through an iTunes account.
Contact Apple Support and request a refund by visiting https://getsupport.apple.com/. Select "Billing & Subscriptions", and then select "Subscriptions & Purchases." Follow the prompts to match your request, and Apple Support will help you with getting it resolved.