Air Ticket booking

I booked an air ticket for my girlfriend to go home on the 14 January 2021, when we get to the airport on the day they couldn't find the booking on the system. I had to pay for another ticket and when I checked my emails I found out that the ticket was booked for February 11 but now on trying to get a refund or changing the ticket am getting an email that says no refunds or changes can be made on the ticket.