TFG is treating employees unfairly

Good day

I have a complaint regarding the fix at Middelburg mall in Mpumalanga ,my brother was an employee there and got dismissed last year November 2023 on Black Friday He was told that he was told that the reason was that he used the same ID number to get rewards for customers, TFG has this rewards system they use before a customer can purchase any item in store so some customers prefer not to give their ID number when purchasing so he got into trouble for not adding any ID number for rewards to a purchase then somehow he decided to use a certain ID number for purchases cause some customers prefer not to use their ID number before purchase So now the problem is that he received a text from his Manager from the Fix at Middelburg mall saying that he has a debt to settle whereby he has no idea of what’s the debt about, please assist cause now he’s being accused for something he knows nothing about.