Standard Bank *********** staff

I recently purchased flight tickets to Australia with Standard Bank. Standard bank has an offer that is you purchase tickets with Emirates, you get 20% off. I went into the branch and a consultant by the name of Preshenka Naidoo assisted me and told me how to purchase the tickets, following her instructions I made the purchase but did not receive my discount. I enquired worry Standard bank on this and they said that I was supposed to purchase the tickets via their Leisure desk. I went back to the branch and told the consultant that she had misinformed me and she still insisted that she knows nothing about a leisure desk and that she purchased tickets on the app and received her 20% discount. My discount is over R5000 and I want my money back. It has been reported on the 17th Dec, and to date, Standard bank has not resolved the issue. It is not fair that clients should pay the cost of companies having untrained staff who misinform clients, costing us thousands of hard earned money. I want a resolution and my money back. I am fed up of waiting for them to get back to me with a solution.