Disappointed with Yamuna Travels

I am disappointed with the service I received from Yamuna Travels. I booked an air ticket from China to SA. My local flight was booked from Jhb to Durban was booked with SA Fair, The travel agent did not book my luggage online as a result I had to pay a fee at the airport. The agent said she will lodge a complaint. I explained that according to airline rules , luggage must be booked online . I requested a refund. Yamuna Travels refuses to take responsibility.