FNB's ridiculous requirements

FNB have made an error on my account. I queried it via the phone app, but they refused to lodge a query on my behalf. I then phoned in, and that consultant too refused to lodge my query. The consultant I spoke to wanted me to do their verification, and I refuse to do this. FNB are always saying that they will never ask you for your PIN, and then they ask me to put in my PIN over the phone when they verify you. It is incredibly unreasonable and on top of that, unsafe for clients too. And they are just unable to put themselves in their clients'shoes to understand the problem.