Deceptive conduct.

I am currently paying the interest on my sisters student loan. before agreeing to signing my name on the contract I confirmed with the standard bank consultant that it will reflect on my credit score and improve it. It has been roughly 2/3 months and I have not even see the standard bank student loan reflect on my credit score report, there is not even a single detail of me paying off the surety of this loan. I contacted the credit bureau and they have emailed me back saying that they have not receive such from standard bank. I do request that this gets sorted out because I am trying my best to build my credit score to actually apply for credit, this has put a stop in my credit improvement journey and it is really inconvenient for myself. If I was falsely informed by a standard bank employee that me paying for the surety of this loan will affect my credit score positively then legal action will be taken as this would be deceptive conduct. Please get back to me.