FND poor customer service

I went to make a purchase at Makro, and when I got home found that a transaction of R767.49 was processed 2 minutes before I made my purchase. I immediately called the FNB ***** Line and have been waiting for them to answer for 20 minutes. I tried logging it via their banking app but get told to access the ***** link, and when I try that, it asks me to download the app, yet I have been using it for years!