How to Receive Refund for FlixBus Ticket

I purchased a FlixBus ticket on November 6, 2024, for my guest traveling from Essen to Mannheim. However, my guest decided not to proceed with the trip. When I requested a refund, FlixBus provided a voucher (Gutschein) valid for one year instead of returning the money.

I do not use buses for travel in Germany, so the voucher is of no use to me. I asked for a proper refund, knowing they already deduct fees for cancellations, but they outright refused. This policy feels unfair, as my money is now wasted on a service I cannot use. I am requesting FlixBus to reconsider and issue a refund for the ticket cost.