Ticket from UK to SA

We booked for a ticket for our son to fly back from UK to SA. The misleading information is that you can book in a 23 kg bag and 1 hand luggage only to discover no suitcase was allowed for this ticket. We tried to rectify and no option was given at all. We tried to add an extra bag but they had a technical issue and we were unable to add an extra hand luggage. No service available at all. DO NOT EVER USE THIS AIRLINE THEY ARE SHOCKING.