Query of pricing for rectifications in the airline ticket and accessing of rectification

Good day,

Today, I made an error with the ticket that I was booking, which I had to pay an amount of R1150.00 just for changing a surname not changing the whole ticket details.. It came as a shock to me that you do not have a provision of human error such rectifying surname or a name or email and you will charge such an amount. I am raising this because it is not fair and inequitable. I would understand if I was changing the whole passenger details or the whole ticket but an error of 'SURNAME'☹️☹️☹️...