Wrong mathematics marks in final school report

After having my son receive wrong marks for his final exam in mathematics in grade 9 last year ,I was promised that his report will be re- issued and amended. This happened last year December and up until today I still can't find the amended school report because they are investigating. My son is going to Grade 10 this year however he will not be able to go into the stream of science and maths as per the wrong report....I'm being made a fool by the principal by telling me that they will send my son to the correct stream this year however the school report hasn't been amended....My concern is that how many school kid get wrong marks allocated on their reports and end up failing grades due to the teacher's error..?