The short answer
Here's how to fix an error on an ID document.
The whole question
My sister was born on the 03/11/1959, but her ID states her birthdate is 03/11/1960. What can she do about changing or rectifying the error on her ID?
The long answer
Thank you for your message asking how your sister can correct the error in her ID.
She must go to any Home Affairs office and fill in Form B1-9 and Form BH-309.
She must take proof of the error which shows the correct information, like a birth certificate.
If it’s not a smart card office, she will need to take two identical colour ID photographs. If it is a smart card office they can do it digitally.