Extremely rude and poor service, no care for elderly

Extremely poor service and confrontational: I will be informing all friends family and acquaintances never to fly with this airline. incident happened at OR Thambo airport in Johannesburg South Africa at around 15h00 on the 3rd of September 2022. My mother booked to fly on this useless airline including airline assistance with wheelchair and special diet as she is diabetic. She is 80 years old, has just recovered from a broken leg. When I went to BA check in I spoke with a BA check in attendant by the name of Charles a coloured male stationed at A50, he was chatting with other staff members and not doing his job. people were queuing and he was ignoring them, he was very rude and actually wanted to confront me. He eventually state he will call a wheelchair attendant to the front. I waited for half an hour, no wheelchair arrived. My mother was forced to walk an extremely long distance in her condition. Sadly the Swiss Air guys tried to help with a wheel chair as they were going to fetch and aid there passengers, this is a disgrace to the British people where my mom comes from that the airline that carries this name provides such atrocious service. When My mom inquired at another check in counter regarding her diet she was simply told how must I know, I don't set the menu so why you asking me. There was a lady walking around who acted as a supervisor who simply ignored me when I tried to ask for assistance. British Airways shame on you and your service.