Refund refusal

Ref number: B4FT8DLR/L4EGNQZT. I have bought the ticket of above Ref number on the 5th Dec at 17:45 as I was attending an interview which was then cancelled in the following day, leading me to cancel the ticket as well. Now I cant get refund due to the 72hour Policy, How was I supposed to cancel my ticket within 72 hours whilst I had less dan 24 hours with it. What is even worse I dont even travel with buses most of the time, since am driving, for me to buy this ticket I got discharged in hospital on Wednesday. My most concern is there's no Greyhound offices in Mossel Bay, I cant even ask a stranger to use the voucher so that I can get my money back. I agree on the policy of a 20% fine, because of an inconvenience but refusing to give my money is very unfair. The 72 hour policy should be revised for customers having tickets less tha those hours. It would be easy for Greyhound offices to use the voucher to other customers since they have access to everyday customer's bookings. I am in need of my money, I don't need voucher that I won't be able to use.